[Chromecast] Reactive WebContents presentation.

No more detatchWebContentsIfAny() and similar helpers.
This boils the presentation of WebContents into a simple state
machine compatible with Observables.

This refactor includes covering the business logic of
CastWebContentsSurfaceHelper in unittests. The implementation
details of CastWebContentsView are still not unit-tested, but
are now better isolated from other logic.

Bug: Internal b/36777136
Test: cast_shell_junit_tests
Change-Id: Ia555b4d3ea9ee07607bf54cc339b950fe068d220
Reviewed-on: https://chromium-review.googlesource.com/1003412Reviewed-by: Luke Halliwell <halliwell@chromium.org>
Commit-Queue: Simeon Anfinrud <sanfin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#551464}

chromecast/browser/android/BUILD.gn

@@ -112,6 +112,7 @@ android_library("cast_shell_java") {
     "$java_src_dir/org/chromium/chromecast/shell/CastWebContentsIntentUtils.java",
     "$java_src_dir/org/chromium/chromecast/shell/CastWebContentsService.java",
     "$java_src_dir/org/chromium/chromecast/shell/CastWebContentsSurfaceHelper.java",
+    "$java_src_dir/org/chromium/chromecast/shell/CastWebContentsView.java",
     "$java_src_dir/org/chromium/chromecast/shell/LogcatElision.java",
     "$java_src_dir/org/chromium/chromecast/shell/ElidedLogcatProvider.java",
   ]
@@ -160,6 +161,7 @@ junit_binary("cast_shell_junit_tests") {
     "junit/src/org/chromium/chromecast/shell/CastWebContentsActivityTest.java",
     "junit/src/org/chromium/chromecast/shell/CastWebContentsComponentTest.java",
     "junit/src/org/chromium/chromecast/shell/CastWebContentsIntentUtilsTest.java",
+    "junit/src/org/chromium/chromecast/shell/CastWebContentsSurfaceHelperTest.java",
     "junit/src/org/chromium/chromecast/shell/LocalBroadcastReceiverScopeTest.java",
     "junit/src/org/chromium/chromecast/shell/LogcatElisionUnitTest.java",
     "junit/src/org/chromium/chromecast/shell/ElidedLogcatProviderUnitTest.java",

chromecast/browser/android/apk/src/org/chromium/chromecast/shell/CastWebContentsActivity.java

@@ -7,7 +7,9 @@ package org.chromium.chromecast.shell;
 import android.app.Activity;
 import android.content.Intent;
 import android.content.IntentFilter;
+import android.graphics.Color;
 import android.media.AudioManager;
+import android.net.Uri;
 import android.os.Bundle;
 import android.view.KeyEvent;
 import android.view.MotionEvent;
@@ -19,6 +21,7 @@ import android.widget.Toast;
 import org.chromium.base.Log;
 import org.chromium.base.annotations.RemovableInRelease;
 import org.chromium.chromecast.base.Both;
+import org.chromium.chromecast.base.CastSwitches;
 import org.chromium.chromecast.base.Controller;
 import org.chromium.chromecast.base.Observable;
 import org.chromium.chromecast.base.ScopeFactories;
@@ -86,8 +89,12 @@ public class CastWebContentsActivity extends Activity {
                     setContentView(R.layout.cast_web_contents_activity);
 
                     mSurfaceHelper = new CastWebContentsSurfaceHelper(this, /* hostActivity */
-                            (FrameLayout) findViewById(R.id.web_contents_container),
-                            false /* showInFragment */);
+                            CastWebContentsView.onLayout(getApplicationContext(),
+                                    (FrameLayout) findViewById(R.id.web_contents_container),
+                                    CastSwitches.getSwitchValueColor(
+                                            CastSwitches.CAST_APP_BACKGROUND_COLOR, Color.BLACK),
+                                    mResumedState),
+                            (Uri uri) -> mIsFinishingState.set("Delayed teardown for URI: " + uri));
                 }));
 
         // Initialize the audio manager in onCreate() if tests haven't already.
@@ -157,9 +164,6 @@ public class CastWebContentsActivity extends Activity {
         if (DEBUG) Log.d(TAG, "onPause");
         super.onPause();
         mResumedState.reset();
-        if (mSurfaceHelper != null) {
-            mSurfaceHelper.onPause();
-        }
     }
 
     @Override
@@ -167,9 +171,6 @@ public class CastWebContentsActivity extends Activity {
         if (DEBUG) Log.d(TAG, "onResume");
         super.onResume();
         mResumedState.set(Unit.unit());
-        if (mSurfaceHelper != null) {
-            mSurfaceHelper.onResume();
-        }
     }
 
     @Override

chromecast/browser/android/apk/src/org/chromium/chromecast/shell/CastWebContentsFragment.java

@@ -7,6 +7,8 @@ package org.chromium.chromecast.shell;
 import android.app.Fragment;
 import android.content.Context;
 import android.content.Intent;
+import android.graphics.Color;
+import android.net.Uri;
 import android.os.Bundle;
 import android.view.LayoutInflater;
 import android.view.View;
@@ -16,6 +18,9 @@ import android.widget.Toast;
 
 import org.chromium.base.ContextUtils;
 import org.chromium.base.Log;
+import org.chromium.chromecast.base.CastSwitches;
+import org.chromium.chromecast.base.Controller;
+import org.chromium.chromecast.base.Unit;
 
 /**
  * Fragment for displaying a WebContents in CastShell.
@@ -31,14 +36,12 @@ import org.chromium.base.Log;
 public class CastWebContentsFragment extends Fragment {
     private static final String TAG = "cr_CastWebContentFrg";
 
-    private Context mPackageContext;
+    private final Controller<Unit> mResumedState = new Controller<>();
 
+    private Context mPackageContext;
     private CastWebContentsSurfaceHelper mSurfaceHelper;
-
     private View mFragmentRootView;
-
     private String mAppId;
-
     private int mInitialVisiblityPriority;
 
     @Override
@@ -61,12 +64,11 @@ public class CastWebContentsFragment extends Fragment {
         }
         if (mFragmentRootView == null) {
             mFragmentRootView = inflater.cloneInContext(getContext())
-                .inflate(R.layout.cast_web_contents_activity, null);
+                                        .inflate(R.layout.cast_web_contents_activity, null);
         }
         return mFragmentRootView;
     }
 
-
     @Override
     public Context getContext() {
         if (mPackageContext == null) {
@@ -88,8 +90,13 @@ public class CastWebContentsFragment extends Fragment {
         }
 
         mSurfaceHelper = new CastWebContentsSurfaceHelper(getActivity(), /* hostActivity */
-                    (FrameLayout) getView().findViewById(R.id.web_contents_container),
-                    true /* showInFragment */);
+                CastWebContentsView.onLayout(getContext(),
+                        (FrameLayout) getView().findViewById(R.id.web_contents_container),
+                        CastSwitches.getSwitchValueColor(
+                                CastSwitches.CAST_APP_BACKGROUND_COLOR, Color.BLACK),
+                        mResumedState),
+                (Uri uri) -> sendIntentSync(CastWebContentsIntentUtils.onWebContentStopped(uri)));
+
         Bundle bundle = getArguments();
         CastWebContentsSurfaceHelper.StartParams params =
                 CastWebContentsSurfaceHelper.StartParams.fromBundle(bundle);
@@ -106,18 +113,14 @@ public class CastWebContentsFragment extends Fragment {
     public void onPause() {
         Log.d(TAG, "onPause");
         super.onPause();
-        if (mSurfaceHelper != null) {
-            mSurfaceHelper.onPause();
-        }
+        mResumedState.reset();
     }
 
     @Override
     public void onResume() {
         Log.d(TAG, "onResume");
         super.onResume();
-        if (mSurfaceHelper != null) {
-            mSurfaceHelper.onResume();
-        }
+        mResumedState.set(Unit.unit());
     }
 
     @Override

chromecast/browser/android/apk/src/org/chromium/chromecast/shell/CastWebContentsService.java

@@ -13,13 +13,11 @@ import android.widget.Toast;
 
 import org.chromium.base.Log;
 import org.chromium.base.annotations.JNINamespace;
+import org.chromium.chromecast.base.Both;
 import org.chromium.chromecast.base.Controller;
+import org.chromium.chromecast.base.Observable;
 import org.chromium.chromecast.base.Unit;
-import org.chromium.components.content_view.ContentView;
-import org.chromium.content_public.browser.ContentViewCore;
 import org.chromium.content_public.browser.WebContents;
-import org.chromium.ui.base.ViewAndroidDelegate;
-import org.chromium.ui.base.WindowAndroid;
 
 /**
  * Service for "displaying" a WebContents in CastShell.
@@ -34,11 +32,31 @@ public class CastWebContentsService extends Service {
     private static final int CAST_NOTIFICATION_ID = 100;
 
     private final Controller<Unit> mLifetimeController = new Controller<>();
+    private final Controller<WebContents> mWebContentsState = new Controller<>();
     private String mInstanceId;
     private CastAudioManager mAudioManager;
-    private WindowAndroid mWindow;
-    private ContentViewCore mContentViewCore;
-    private ContentView mContentView;
+
+    {
+        // Construct an Observable that is deactivated when either mWebContentsState or
+        // mLifetimeController is reset, and has the activation data of mWebContentsState.
+        Observable<WebContents> hasWebContentsState =
+                mWebContentsState.and(mLifetimeController).map(Both::getFirst);
+        // React to web contents by presenting them in a headless view.
+        hasWebContentsState.watch(CastWebContentsView.withoutLayout(this));
+        hasWebContentsState.watch(() -> {
+            if (DEBUG) Log.d(TAG, "show web contents");
+            // TODO(thoren): Notification.Builder(Context) is deprecated in O. Use the
+            // (Context, String) constructor when CastWebContentsService starts supporting O.
+            Notification notification = new Notification.Builder(this).build();
+            startForeground(CAST_NOTIFICATION_ID, notification);
+            return () -> {
+                if (DEBUG) Log.d(TAG, "detach web contents");
+                stopForeground(true /*removeNotification*/);
+                // Inform CastContentWindowAndroid we're detaching.
+                CastWebContentsComponent.onComponentClosed(mInstanceId);
+            };
+        });
+    }
 
     protected void handleIntent(Intent intent) {
         intent.setExtrasClassLoader(WebContents.class.getClassLoader());
@@ -50,8 +68,7 @@ public class CastWebContentsService extends Service {
             return;
         }
 
-        detachWebContentsIfAny();
-        showWebContents(webContents);
+        mWebContentsState.set(webContents);
     }
 
     @Override
@@ -65,14 +82,11 @@ public class CastWebContentsService extends Service {
     @Override
     public void onCreate() {
         if (DEBUG) Log.d(TAG, "onCreate");
-
         if (!CastBrowserHelper.initializeBrowser(getApplicationContext())) {
             Toast.makeText(this, R.string.browser_process_initialization_failed, Toast.LENGTH_SHORT)
                     .show();
             stopSelf();
         }
-
-        mWindow = new WindowAndroid(this);
         CastAudioManager.getAudioManager(this).requestAudioFocusWhen(
                 mLifetimeController, AudioManager.STREAM_MUSIC, AudioManager.AUDIOFOCUS_GAIN);
         mLifetimeController.set(Unit.unit());
@@ -81,42 +95,7 @@ public class CastWebContentsService extends Service {
     @Override
     public IBinder onBind(Intent intent) {
         if (DEBUG) Log.d(TAG, "onBind");
-
         handleIntent(intent);
-
         return null;
     }
-
-    // Sets webContents to be the currently displayed webContents.
-    // TODO(thoren): Notification.Builder(Context) is deprecated in O. Use the (Context, String)
-    // constructor when CastWebContentsService starts supporting O.
-    @SuppressWarnings("deprecation")
-    private void showWebContents(WebContents webContents) {
-        if (DEBUG) Log.d(TAG, "showWebContents");
-
-        Notification notification = new Notification.Builder(this).build();
-        startForeground(CAST_NOTIFICATION_ID, notification);
-
-        mContentView = ContentView.createContentView(this, webContents);
-        // TODO(derekjchow): productVersion
-        mContentViewCore = ContentViewCore.create(this, "", webContents,
-                ViewAndroidDelegate.createBasicDelegate(mContentView), mContentView, mWindow);
-        // Enable display of current webContents.
-        webContents.onShow();
-    }
-
-    // Remove the currently displayed webContents. no-op if nothing is being displayed.
-    private void detachWebContentsIfAny() {
-        if (DEBUG) Log.d(TAG, "detachWebContentsIfAny");
-
-        stopForeground(true /*removeNotification*/);
-
-        if (mContentView != null) {
-            mContentView = null;
-            mContentViewCore = null;
-
-            // Inform CastContentWindowAndroid we're detaching.
-            CastWebContentsComponent.onComponentClosed(mInstanceId);
-        }
-    }
 }

chromecast/browser/android/apk/src/org/chromium/chromecast/shell/CastWebContentsSurfaceHelper.java

@@ -5,29 +5,26 @@
 package org.chromium.chromecast.shell;
 
 import android.app.Activity;
-import android.content.Context;
 import android.content.Intent;
 import android.content.IntentFilter;
-import android.graphics.Color;
 import android.media.AudioManager;
 import android.net.Uri;
 import android.os.Bundle;
 import android.os.Handler;
-import android.widget.FrameLayout;
 
 import org.chromium.base.Log;
 import org.chromium.base.annotations.JNINamespace;
-import org.chromium.chromecast.base.CastSwitches;
+import org.chromium.base.annotations.RemovableInRelease;
+import org.chromium.chromecast.base.Both;
+import org.chromium.chromecast.base.Consumer;
 import org.chromium.chromecast.base.Controller;
+import org.chromium.chromecast.base.Observable;
+import org.chromium.chromecast.base.ScopeFactories;
+import org.chromium.chromecast.base.ScopeFactory;
 import org.chromium.chromecast.base.Unit;
-import org.chromium.components.content_view.ContentView;
 import org.chromium.content.browser.ActivityContentVideoViewEmbedder;
 import org.chromium.content.browser.ContentVideoViewEmbedder;
-import org.chromium.content.browser.ContentViewRenderView;
-import org.chromium.content_public.browser.ContentViewCore;
 import org.chromium.content_public.browser.WebContents;
-import org.chromium.ui.base.ViewAndroidDelegate;
-import org.chromium.ui.base.WindowAndroid;
 
 /**
  * A util class for CastWebContentsActivity and CastWebContentsFragment to show
@@ -47,20 +44,18 @@ class CastWebContentsSurfaceHelper {
 
     private static final int TEARDOWN_GRACE_PERIOD_TIMEOUT_MILLIS = 300;
 
-    private final Controller<Unit> mResumedState = new Controller<>();
+    private final Controller<Unit> mCreatedState = new Controller<>();
+    // Activated when we have an instance URI, from which the instance ID is derived.
+    // Is (re)activated when new StartParams are received, and deactivated in onDestroy().
     private final Controller<Uri> mHasUriState = new Controller<>();
+    // Activated when we have WebContents to display.
+    private final Controller<WebContents> mWebContentsState = new Controller<>();
 
-    private final Activity mHostActivity;
-    private final boolean mShowInFragment;
+    private final Consumer<Uri> mFinishCallback;
     private final Handler mHandler;
-    private final FrameLayout mCastWebContentsLayout;
 
-    private Uri mUri;
     private String mInstanceId;
-    private ContentViewRenderView mContentViewRenderView;
-    private WindowAndroid mWindow;
-    private ContentViewCore mContentViewCore;
-    private ContentView mContentView;
+    private ContentVideoViewEmbedderSetter mContentVideoViewEmbedderSetter;
 
     // TODO(vincentli) interrupt touch event from Fragment's root view when it's false.
     private boolean mTouchInputEnabled = false;
@@ -111,25 +106,24 @@ class CastWebContentsSurfaceHelper {
 
     /**
      * @param hostActivity Activity hosts the view showing WebContents
-     * @param castWebContentsLayout view group to add ContentViewRenderView and ContentView
-     * @param showInFragment true if the cast web view is hosted by a CastWebContentsFragment
+     * @param webContentsView A ScopeFactory that displays incoming WebContents.
+     * @param finishCallback Invoked to tell host to finish.
      */
-    CastWebContentsSurfaceHelper(
-            Activity hostActivity, FrameLayout castWebContentsLayout, boolean showInFragment) {
-        mHostActivity = hostActivity;
-        mShowInFragment = showInFragment;
-        mCastWebContentsLayout = castWebContentsLayout;
-        mCastWebContentsLayout.setBackgroundColor(CastSwitches.getSwitchValueColor(
-                CastSwitches.CAST_APP_BACKGROUND_COLOR, Color.BLACK));
+    CastWebContentsSurfaceHelper(Activity hostActivity, ScopeFactory<WebContents> webContentsView,
+            Consumer<Uri> finishCallback) {
+        mFinishCallback = finishCallback;
         mHandler = new Handler();
+        mContentVideoViewEmbedderSetter =
+                (WebContents webContents, ContentVideoViewEmbedder embedder)
+                -> nativeSetContentVideoViewEmbedder(webContents, embedder);
 
         // Receive broadcasts indicating the screen turned off while we have active WebContents.
-        mHasUriState.watch(() -> {
+        mHasUriState.watch((Uri uri) -> {
             IntentFilter filter = new IntentFilter();
             filter.addAction(CastIntents.ACTION_SCREEN_OFF);
             return new LocalBroadcastReceiverScope(filter, (Intent intent) -> {
-                detachWebContentsIfAny();
-                maybeFinishLater();
+                mWebContentsState.reset();
+                maybeFinishLater(uri);
             });
         });
 
@@ -141,17 +135,16 @@ class CastWebContentsSurfaceHelper {
                 String intentUri = CastWebContentsIntentUtils.getUriString(intent);
                 Log.d(TAG, "Intent action=" + intent.getAction() + "; URI=" + intentUri);
                 if (!uri.toString().equals(intentUri)) {
-                    Log.d(TAG, "Current URI=" + mUri + "; intent URI=" + intentUri);
+                    Log.d(TAG, "Current URI=" + uri + "; intent URI=" + intentUri);
                     return;
                 }
-                detachWebContentsIfAny();
-                maybeFinishLater();
+                mWebContentsState.reset();
+                maybeFinishLater(uri);
             });
         });
 
         // Receive broadcasts indicating that touch input should be enabled.
-        // TODO(yyzhong) Handle this intent in an external activity hosting a cast fragment as
-        // well.
+        // TODO(yyzhong) Handle this intent in an external activity hosting a cast fragment as well.
         mHasUriState.watch((Uri uri) -> {
             IntentFilter filter = new IntentFilter();
             filter.addAction(CastWebContentsIntentUtils.ACTION_ENABLE_TOUCH_INPUT);
@@ -159,141 +152,64 @@ class CastWebContentsSurfaceHelper {
                 String intentUri = CastWebContentsIntentUtils.getUriString(intent);
                 Log.d(TAG, "Intent action=" + intent.getAction() + "; URI=" + intentUri);
                 if (!uri.toString().equals(intentUri)) {
-                    Log.d(TAG, "Current URI=" + mUri + "; intent URI=" + intentUri);
+                    Log.d(TAG, "Current URI=" + uri + "; intent URI=" + intentUri);
                     return;
                 }
                 mTouchInputEnabled = CastWebContentsIntentUtils.isTouchable(intent);
             });
         });
 
-        mResumedState.watch(() -> {
-            if (mContentViewCore != null) {
-                mContentViewCore.onResume();
-            }
-            return () -> {
-                if (mContentViewCore != null) {
-                    mContentViewCore.onPause();
-                }
-            };
+        // webContentsView is responsible for displaying each new WebContents.
+        mWebContentsState.watch(webContentsView);
+
+        // Miscellaneous actions responding to WebContents lifecycle.
+        mWebContentsState.watch((WebContents webContents) -> {
+            // Set ContentVideoViewEmbedder to allow video playback.
+            mContentVideoViewEmbedderSetter.set(
+                    webContents, new ActivityContentVideoViewEmbedder(hostActivity));
+            // Whenever our app is visible, volume controls should modify the music stream.
+            // For more information read:
+            // http://developer.android.com/training/managing-audio/volume-playback.html
+            hostActivity.setVolumeControlStream(AudioManager.STREAM_MUSIC);
+            // Notify CastWebContentsComponent when closed.
+            return () -> CastWebContentsComponent.onComponentClosed(mInstanceId);
         });
+
+        // When onDestroy() is called after onNewStartParams(), log and reset StartParams states.
+        mHasUriState.andThen(Observable.not(mCreatedState))
+                .map(Both::getFirst)
+                .watch(ScopeFactories.onEnter((Uri uri) -> {
+                    Log.d(TAG, "onDestroy: " + uri);
+                    mWebContentsState.reset();
+                    mHasUriState.reset();
+                }));
+
+        mCreatedState.set(Unit.unit());
     }
 
     void onNewStartParams(final StartParams params) {
         mTouchInputEnabled = params.touchInputEnabled;
         Log.d(TAG, "content_uri=" + params.uri);
-        mUri = params.uri;
+        mHasUriState.set(params.uri);
+        mWebContentsState.set(params.webContents);
+        // Mutate instance ID cache only after observers have reacted to new web contents.
         mInstanceId = params.uri.getPath();
-
-        // Whenever our app is visible, volume controls should modify the music stream.
-        // For more information read:
-        // http://developer.android.com/training/managing-audio/volume-playback.html
-        mHostActivity.setVolumeControlStream(AudioManager.STREAM_MUSIC);
-
-        mHasUriState.set(mUri);
-
-        showWebContents(params.webContents);
     }
 
     // Closes this activity if a new WebContents is not being displayed.
-    private void maybeFinishLater() {
-        Log.d(TAG, "maybeFinishLater: " + mUri);
+    private void maybeFinishLater(Uri uri) {
+        Log.d(TAG, "maybeFinishLater: " + uri);
         final String currentInstanceId = mInstanceId;
-        mHandler.postDelayed(new Runnable() {
-            @Override
-            public void run() {
-                if (currentInstanceId != null && currentInstanceId.equals(mInstanceId)) {
-                    if (mShowInFragment) {
-                        Log.d(TAG, "Sending intent: ON_WEB_CONTENT_STOPPED: URI=" + mUri);
-                        CastWebContentsIntentUtils.getLocalBroadcastManager().sendBroadcastSync(
-                                CastWebContentsIntentUtils.onWebContentStopped(mUri));
-                    } else {
-                        Log.d(TAG, "Finishing cast content activity of URI:" + mUri);
-                        mHostActivity.finish();
-                    }
-                }
+        mHandler.postDelayed(() -> {
+            if (currentInstanceId != null && currentInstanceId.equals(mInstanceId)) {
+                mFinishCallback.accept(uri);
             }
         }, TEARDOWN_GRACE_PERIOD_TIMEOUT_MILLIS);
     }
 
-    private Activity getActivity() {
-        return mHostActivity;
-    }
-
-    // Sets webContents to be the currently displayed webContents.
-    private void showWebContents(WebContents webContents) {
-        Log.d(TAG, "showWebContents: " + mUri);
-
-        detachWebContentsIfAny();
-
-        // Set ContentVideoViewEmbedder to allow video playback.
-        nativeSetContentVideoViewEmbedder(
-                webContents, new ActivityContentVideoViewEmbedder(getActivity()));
-
-        mWindow = new WindowAndroid(getActivity());
-        mContentViewRenderView = new ContentViewRenderView(getActivity()) {
-            @Override
-            protected void onReadyToRender() {
-                setOverlayVideoMode(true);
-            }
-        };
-        mContentViewRenderView.onNativeLibraryLoaded(mWindow);
-        // Setting the background color avoids rendering a white splash screen
-        // before the players are loaded. See https://crbug/307113 for details.
-        mContentViewRenderView.setSurfaceViewBackgroundColor(CastSwitches.getSwitchValueColor(
-                CastSwitches.CAST_APP_BACKGROUND_COLOR, Color.BLACK));
-
-        mCastWebContentsLayout.addView(mContentViewRenderView,
-                new FrameLayout.LayoutParams(FrameLayout.LayoutParams.MATCH_PARENT,
-                        FrameLayout.LayoutParams.MATCH_PARENT));
-
-        Context context = getActivity().getApplicationContext();
-        mContentView = ContentView.createContentView(context, webContents);
-        // TODO(derekjchow): productVersion
-        mContentViewCore = ContentViewCore.create(context, "", webContents,
-                ViewAndroidDelegate.createBasicDelegate(mContentView), mContentView, mWindow);
-        // Enable display of current webContents.
-        webContents.onShow();
-        mCastWebContentsLayout.addView(mContentView,
-                new FrameLayout.LayoutParams(FrameLayout.LayoutParams.MATCH_PARENT,
-                        FrameLayout.LayoutParams.MATCH_PARENT));
-        mContentView.setFocusable(true);
-        mContentView.requestFocus();
-        mContentViewRenderView.setCurrentWebContents(webContents);
-    }
-
-    // Remove the currently displayed webContents. no-op if nothing is being displayed.
-    private void detachWebContentsIfAny() {
-        Log.d(TAG, "Maybe detach web contents if any: " + mUri);
-        if (mContentView != null) {
-            mCastWebContentsLayout.removeView(mContentView);
-            mCastWebContentsLayout.removeView(mContentViewRenderView);
-            mContentViewCore.destroy();
-            mContentViewRenderView.destroy();
-            mWindow.destroy();
-            mContentView = null;
-            mContentViewCore = null;
-            mContentViewRenderView = null;
-            mWindow = null;
-            CastWebContentsComponent.onComponentClosed(mInstanceId);
-            Log.d(TAG, "Detach web contents done: " + mUri);
-        }
-    }
-
-    void onPause() {
-        Log.d(TAG, "onPause: " + mUri);
-        mResumedState.reset();
-    }
-
-    void onResume() {
-        Log.d(TAG, "onResume: " + mUri);
-        mResumedState.set(Unit.unit());
-    }
-
     // Destroys all resources. After calling this method, this object must be dropped.
     void onDestroy() {
-        Log.d(TAG, "onDestroy: " + mUri);
-        detachWebContentsIfAny();
-        mHasUriState.reset();
+        mCreatedState.reset();
     }
 
     String getInstanceId() {
@@ -304,6 +220,15 @@ class CastWebContentsSurfaceHelper {
         return mTouchInputEnabled;
     }
 
+    @RemovableInRelease
+    void setContentVideoViewEmbedderSetterForTesting(ContentVideoViewEmbedderSetter cvves) {
+        mContentVideoViewEmbedderSetter = cvves;
+    }
+
+    interface ContentVideoViewEmbedderSetter {
+        void set(WebContents webContents, ContentVideoViewEmbedder embedder);
+    }
+
     private native void nativeSetContentVideoViewEmbedder(
             WebContents webContents, ContentVideoViewEmbedder embedder);
 }

chromecast/browser/android/apk/src/org/chromium/chromecast/shell/CastWebContentsView.java

+// Copyright 2018 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.chromecast.shell;
+
+import android.content.Context;
+import android.widget.FrameLayout;
+
+import org.chromium.chromecast.base.Observable;
+import org.chromium.chromecast.base.ScopeFactory;
+import org.chromium.components.content_view.ContentView;
+import org.chromium.content.browser.ContentViewRenderView;
+import org.chromium.content_public.browser.ContentViewCore;
+import org.chromium.content_public.browser.WebContents;
+import org.chromium.ui.base.ViewAndroidDelegate;
+import org.chromium.ui.base.WindowAndroid;
+
+class CastWebContentsView {
+    public static ScopeFactory<WebContents> onLayout(
+            Context context, FrameLayout layout, int backgroundColor, Observable<?> resumedState) {
+        layout.setBackgroundColor(backgroundColor);
+        return (WebContents webContents) -> {
+            WindowAndroid window = new WindowAndroid(context);
+            ContentViewRenderView contentViewRenderView = new ContentViewRenderView(context) {
+                @Override
+                protected void onReadyToRender() {
+                    setOverlayVideoMode(true);
+                }
+            };
+            contentViewRenderView.onNativeLibraryLoaded(window);
+            contentViewRenderView.setSurfaceViewBackgroundColor(backgroundColor);
+            FrameLayout.LayoutParams matchParent = new FrameLayout.LayoutParams(
+                    FrameLayout.LayoutParams.MATCH_PARENT, FrameLayout.LayoutParams.MATCH_PARENT);
+            layout.addView(contentViewRenderView, matchParent);
+
+            ContentView contentView = ContentView.createContentView(context, webContents);
+            // TODO(derekjchow): productVersion
+            ContentViewCore contentViewCore = ContentViewCore.create(context, "", webContents,
+                    ViewAndroidDelegate.createBasicDelegate(contentView), contentView, window);
+
+            // Enable display of current webContents.
+            webContents.onShow();
+            layout.addView(contentView, matchParent);
+            contentView.setFocusable(true);
+            contentView.requestFocus();
+            contentViewRenderView.setCurrentWebContents(webContents);
+            resumedState.watch(() -> {
+                contentViewCore.onResume();
+                return contentViewCore::onPause;
+            });
+            return () -> {
+                layout.removeView(contentView);
+                layout.removeView(contentViewRenderView);
+                contentViewCore.destroy();
+                contentViewRenderView.destroy();
+                window.destroy();
+            };
+        };
+    }
+
+    public static ScopeFactory<WebContents> withoutLayout(Context context) {
+        return (WebContents webContents) -> {
+            WindowAndroid window = new WindowAndroid(context);
+            ContentView contentView = ContentView.createContentView(context, webContents);
+            // TODO(derekjchow): productVersion
+            ContentViewCore contentViewCore = ContentViewCore.create(context, "", webContents,
+                    ViewAndroidDelegate.createBasicDelegate(contentView), contentView, window);
+            // Enable display of current webContents.
+            webContents.onShow();
+            return webContents::onHide;
+        };
+    }
+}

chromecast/browser/android/junit/src/org/chromium/chromecast/shell/CastWebContentsSurfaceHelperTest.java

+// Copyright 2018 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.chromecast.shell;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertTrue;
+import static org.mockito.Mockito.any;
+import static org.mockito.Mockito.eq;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+import android.app.Activity;
+import android.content.Intent;
+import android.content.IntentFilter;
+import android.media.AudioManager;
+import android.net.Uri;
+import android.os.PatternMatcher;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.mockito.MockitoAnnotations;
+import org.robolectric.annotation.Config;
+import org.robolectric.shadows.ShadowLooper;
+
+import org.chromium.chromecast.base.Consumer;
+import org.chromium.chromecast.base.Scope;
+import org.chromium.chromecast.base.ScopeFactory;
+import org.chromium.chromecast.shell.CastWebContentsSurfaceHelper.ContentVideoViewEmbedderSetter;
+import org.chromium.chromecast.shell.CastWebContentsSurfaceHelper.StartParams;
+import org.chromium.content.browser.ContentVideoViewEmbedder;
+import org.chromium.content_public.browser.WebContents;
+import org.chromium.testing.local.LocalRobolectricTestRunner;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Tests for CastWebContentsSurfaceHelper.
+ */
+@RunWith(LocalRobolectricTestRunner.class)
+@Config(manifest = Config.NONE)
+public class CastWebContentsSurfaceHelperTest {
+    private @Mock Activity mActivity;
+    private @Mock ScopeFactory<WebContents> mWebContentsView;
+    private @Mock Consumer<Uri> mFinishCallback;
+    private CastWebContentsSurfaceHelper mSurfaceHelper;
+    private @Mock ContentVideoViewEmbedderSetter mContentVideoViewEmbedderSetter;
+
+    private static class StartParamsBuilder {
+        private String mId = "0";
+        private WebContents mWebContents = mock(WebContents.class);
+        private boolean mIsTouchInputEnabled = false;
+
+        public StartParamsBuilder withId(String id) {
+            mId = id;
+            return this;
+        }
+
+        public StartParamsBuilder withWebContents(WebContents webContents) {
+            mWebContents = webContents;
+            return this;
+        }
+
+        public StartParamsBuilder enableTouchInput(boolean enableTouchInput) {
+            mIsTouchInputEnabled = enableTouchInput;
+            return this;
+        }
+
+        public StartParams build() {
+            return new StartParams(CastWebContentsIntentUtils.getInstanceUri(mId), mWebContents,
+                    mIsTouchInputEnabled);
+        }
+    }
+
+    private static class BroadcastAsserter {
+        private final Intent mExpectedIntent;
+        private final List<Intent> mReceivedIntents = new ArrayList<>();
+        private final LocalBroadcastReceiverScope mReceiver;
+
+        public BroadcastAsserter(Intent looksLike) {
+            mExpectedIntent = looksLike;
+            IntentFilter filter = new IntentFilter();
+            Uri instanceUri = looksLike.getData();
+            filter.addDataScheme(instanceUri.getScheme());
+            filter.addDataAuthority(instanceUri.getAuthority(), null);
+            filter.addDataPath(instanceUri.getPath(), PatternMatcher.PATTERN_LITERAL);
+            filter.addAction(looksLike.getAction());
+            mReceiver = new LocalBroadcastReceiverScope(filter, mReceivedIntents::add);
+        }
+
+        public void verify() {
+            assertEquals(1, mReceivedIntents.size());
+            Intent receivedIntent = mReceivedIntents.get(0);
+            assertEquals(mExpectedIntent.getAction(), receivedIntent.getAction());
+            assertEquals(mExpectedIntent.getData(), receivedIntent.getData());
+            mReceiver.close();
+        }
+    }
+
+    private void sendBroadcastSync(Intent intent) {
+        CastWebContentsIntentUtils.getLocalBroadcastManager().sendBroadcastSync(intent);
+    }
+
+    @Before
+    public void setUp() {
+        MockitoAnnotations.initMocks(this);
+        mSurfaceHelper =
+                new CastWebContentsSurfaceHelper(mActivity, mWebContentsView, mFinishCallback);
+        mSurfaceHelper.setContentVideoViewEmbedderSetterForTesting(mContentVideoViewEmbedderSetter);
+    }
+
+    @Test
+    public void testActivatesWebContentsViewOnNewStartParams() {
+        WebContents webContents = mock(WebContents.class);
+        StartParams params = new StartParamsBuilder().withWebContents(webContents).build();
+        mSurfaceHelper.onNewStartParams(params);
+        verify(mWebContentsView).create(webContents);
+    }
+
+    @Test
+    public void testDeactivatesOldWebContentsViewOnNewStartParams() {
+        WebContents webContents1 = mock(WebContents.class);
+        StartParams params1 =
+                new StartParamsBuilder().withId("1").withWebContents(webContents1).build();
+        WebContents webContents2 = mock(WebContents.class);
+        StartParams params2 =
+                new StartParamsBuilder().withId("2").withWebContents(webContents2).build();
+        Scope scope1 = mock(Scope.class);
+        Scope scope2 = mock(Scope.class);
+        when(mWebContentsView.create(webContents1)).thenReturn(scope1);
+        when(mWebContentsView.create(webContents2)).thenReturn(scope2);
+        mSurfaceHelper.onNewStartParams(params1);
+        verify(mWebContentsView).create(webContents1);
+        mSurfaceHelper.onNewStartParams(params2);
+        verify(scope1).close();
+        verify(mWebContentsView).create(webContents2);
+    }
+
+    @Test
+    public void testSetsContentVideoViewEmbedderOnNewStartParams() {
+        WebContents webContents = mock(WebContents.class);
+        StartParams params = new StartParamsBuilder().withWebContents(webContents).build();
+        mSurfaceHelper.onNewStartParams(params);
+        verify(mContentVideoViewEmbedderSetter)
+                .set(eq(webContents), any(ContentVideoViewEmbedder.class));
+    }
+
+    @Test
+    public void testIsTouchInputEnabled() {
+        assertFalse(mSurfaceHelper.isTouchInputEnabled());
+        StartParams params1 = new StartParamsBuilder().enableTouchInput(true).build();
+        mSurfaceHelper.onNewStartParams(params1);
+        assertTrue(mSurfaceHelper.isTouchInputEnabled());
+        StartParams params2 = new StartParamsBuilder().enableTouchInput(false).build();
+        mSurfaceHelper.onNewStartParams(params2);
+        assertFalse(mSurfaceHelper.isTouchInputEnabled());
+    }
+
+    @Test
+    public void testInstanceId() {
+        assertNull(mSurfaceHelper.getInstanceId());
+        StartParams params1 = new StartParamsBuilder().withId("/0").build();
+        mSurfaceHelper.onNewStartParams(params1);
+        assertEquals("/0", mSurfaceHelper.getInstanceId());
+        StartParams params2 = new StartParamsBuilder().withId("/1").build();
+        mSurfaceHelper.onNewStartParams(params2);
+        assertEquals("/1", mSurfaceHelper.getInstanceId());
+    }
+
+    @Test
+    public void testScreenOffResetsWebContentsView() {
+        WebContents webContents = mock(WebContents.class);
+        StartParams params = new StartParamsBuilder().withWebContents(webContents).build();
+        Scope scope = mock(Scope.class);
+        when(mWebContentsView.create(webContents)).thenReturn(scope);
+        mSurfaceHelper.onNewStartParams(params);
+        // Send SCREEN_OFF broadcast.
+        sendBroadcastSync(new Intent(CastIntents.ACTION_SCREEN_OFF));
+        verify(scope).close();
+    }
+
+    @Test
+    public void testStopWebContentsIntentResetsWebContentsView() {
+        WebContents webContents = mock(WebContents.class);
+        StartParams params =
+                new StartParamsBuilder().withId("3").withWebContents(webContents).build();
+        Scope scope = mock(Scope.class);
+        when(mWebContentsView.create(webContents)).thenReturn(scope);
+        mSurfaceHelper.onNewStartParams(params);
+        // Send notification to stop web content
+        sendBroadcastSync(CastWebContentsIntentUtils.requestStopWebContents("3"));
+        verify(scope).close();
+    }
+
+    @Test
+    public void testStopWebContentsIntentWithWrongIdIsIgnored() {
+        WebContents webContents = mock(WebContents.class);
+        StartParams params =
+                new StartParamsBuilder().withId("2").withWebContents(webContents).build();
+        Scope scope = mock(Scope.class);
+        when(mWebContentsView.create(webContents)).thenReturn(scope);
+        mSurfaceHelper.onNewStartParams(params);
+        // Send notification to stop web content with different ID.
+        sendBroadcastSync(CastWebContentsIntentUtils.requestStopWebContents("4"));
+        verify(scope, never()).close();
+    }
+
+    @Test
+    public void testEnableTouchInputIntentMutatesIsTouchInputEnabled() {
+        WebContents webContents = mock(WebContents.class);
+        StartParams params = new StartParamsBuilder().withId("1").enableTouchInput(false).build();
+        mSurfaceHelper.onNewStartParams(params);
+        assertFalse(mSurfaceHelper.isTouchInputEnabled());
+        // Send broadcast to enable touch input.
+        sendBroadcastSync(CastWebContentsIntentUtils.enableTouchInput("1", true));
+        assertTrue(mSurfaceHelper.isTouchInputEnabled());
+    }
+
+    @Test
+    public void testEnableTouchInputIntentWithWrongIdIsIgnored() {
+        WebContents webContents = mock(WebContents.class);
+        StartParams params = new StartParamsBuilder().withId("1").enableTouchInput(false).build();
+        mSurfaceHelper.onNewStartParams(params);
+        assertFalse(mSurfaceHelper.isTouchInputEnabled());
+        // Send broadcast to enable touch input with different ID.
+        sendBroadcastSync(CastWebContentsIntentUtils.enableTouchInput("2", true));
+        assertFalse(mSurfaceHelper.isTouchInputEnabled());
+    }
+
+    @Test
+    public void testDisableTouchInputIntent() {
+        WebContents webContents = mock(WebContents.class);
+        StartParams params = new StartParamsBuilder().withId("1").enableTouchInput(true).build();
+        mSurfaceHelper.onNewStartParams(params);
+        assertTrue(mSurfaceHelper.isTouchInputEnabled());
+        // Send broadcast to enable touch input.
+        sendBroadcastSync(CastWebContentsIntentUtils.enableTouchInput("1", false));
+        assertFalse(mSurfaceHelper.isTouchInputEnabled());
+    }
+
+    @Test
+    public void testSetsVolumeControlStreamOfHostActivity() {
+        StartParams params = new StartParamsBuilder().build();
+        mSurfaceHelper.onNewStartParams(params);
+        verify(mActivity).setVolumeControlStream(AudioManager.STREAM_MUSIC);
+    }
+
+    @Test
+    public void testSendsComponentClosedBroadcastWhenWebContentsViewIsClosedAlt() {
+        StartParams params1 = new StartParamsBuilder().withId("1").build();
+        StartParams params2 = new StartParamsBuilder().withId("2").build();
+        mSurfaceHelper.onNewStartParams(params1);
+        // Listen for notification from surface helper that web contents closed.
+        BroadcastAsserter intentWasSent =
+                new BroadcastAsserter(CastWebContentsIntentUtils.onActivityStopped("1"));
+        mSurfaceHelper.onNewStartParams(params2);
+        intentWasSent.verify();
+    }
+
+    @Test
+    public void testFinishLaterCallbackIsRunAfterStopWebContents() {
+        StartParams params = new StartParamsBuilder().withId("0").build();
+        mSurfaceHelper.onNewStartParams(params);
+        sendBroadcastSync(CastWebContentsIntentUtils.requestStopWebContents("0"));
+        ShadowLooper.runUiThreadTasksIncludingDelayedTasks();
+        verify(mFinishCallback).accept(CastWebContentsIntentUtils.getInstanceUri("0"));
+    }
+
+    @Test
+    public void testFinishLaterCallbackIsRunAfterScreenOff() {
+        StartParams params = new StartParamsBuilder().withId("0").build();
+        mSurfaceHelper.onNewStartParams(params);
+        sendBroadcastSync(new Intent(CastIntents.ACTION_SCREEN_OFF));
+        ShadowLooper.runUiThreadTasksIncludingDelayedTasks();
+        verify(mFinishCallback).accept(CastWebContentsIntentUtils.getInstanceUri("0"));
+    }
+
+    @Test
+    public void testFinishLaterCallbackIsNotRunIfNewWebContentsIsReceived() {
+        StartParams params1 = new StartParamsBuilder().withId("1").build();
+        StartParams params2 = new StartParamsBuilder().withId("2").build();
+        mSurfaceHelper.onNewStartParams(params1);
+        sendBroadcastSync(CastWebContentsIntentUtils.requestStopWebContents("1"));
+        mSurfaceHelper.onNewStartParams(params2);
+        ShadowLooper.runUiThreadTasksIncludingDelayedTasks();
+        verify(mFinishCallback, never()).accept(any());
+    }
+
+    @Test
+    public void testOnDestroyClosesWebContentsView() {
+        WebContents webContents = mock(WebContents.class);
+        Scope scope = mock(Scope.class);
+        StartParams params = new StartParamsBuilder().withWebContents(webContents).build();
+        when(mWebContentsView.create(webContents)).thenReturn(scope);
+        mSurfaceHelper.onNewStartParams(params);
+        mSurfaceHelper.onDestroy();
+        verify(scope).close();
+    }
+
+    @Test
+    public void testOnDestroyNotifiesComponent() {
+        StartParams params = new StartParamsBuilder().withId("2").build();
+        mSurfaceHelper.onNewStartParams(params);
+        BroadcastAsserter intentWasSent =
+                new BroadcastAsserter(CastWebContentsIntentUtils.onActivityStopped("2"));
+        mSurfaceHelper.onDestroy();
+        intentWasSent.verify();
+    }
+}