Add APIs to cache navigation info and send via callback

Adds no-op APIs to cache navigation info for custom tabs like
url, title and content screenshot and send them via a callback
to the client app.

BUG=647342

Review-Url: https://codereview.chromium.org/2348573002
Cr-Commit-Position: refs/heads/master@{#419328}

chrome/android/java/res/values/dimens.xml

@@ -317,6 +317,8 @@
     <dimen name="custom_tabs_url_text_size">12sp</dimen>
     <dimen name="custom_tabs_title_text_size">16sp</dimen>
     <dimen name="custom_tabs_bottom_bar_max_height">60dp</dimen>
+    <dimen name="custom_tabs_screenshot_height">300dp</dimen>
+    <dimen name="custom_tabs_screenshot_width">190dp</dimen>
 
     <!-- Favicon dimensions -->
     <dimen name="default_favicon_size">16dp</dimen>

chrome/android/java/src/org/chromium/chrome/browser/customtabs/ClientManager.java

@@ -57,6 +57,7 @@ class ClientManager {
         public boolean mIgnoreFragments;
         private boolean mShouldHideDomain;
         private boolean mShouldPrerenderOnCellular;
+        private boolean mShouldSendNavigationInfo;
         private ServiceConnection mKeepAliveConnection;
         private String mPredictedUrl;
         private long mLastMayLaunchUrlTimestamp;
@@ -250,6 +251,23 @@ class ClientManager {
         if (params != null) params.mShouldHideDomain = hide;
     }
 
+    /**
+     * @return Whether navigation info should be recorded and shared for the session.
+     */
+    public synchronized boolean shouldSendNavigationInfoForSession(CustomTabsSessionToken session) {
+        SessionParams params = mSessionParams.get(session);
+        return params != null ? params.mShouldSendNavigationInfo : false;
+    }
+
+    /**
+     * Sets whether navigation info should be recorded and shared for the session.
+     */
+    public synchronized void setSendNavigationInfoForSession(
+            CustomTabsSessionToken session, boolean save) {
+        SessionParams params = mSessionParams.get(session);
+        if (params != null) params.mShouldSendNavigationInfo = save;
+    }
+
     /**
      * @return Whether the fragment should be ignored for prerender matching.
      */

chrome/android/java/src/org/chromium/chrome/browser/customtabs/CustomTabObserver.java

@@ -5,15 +5,20 @@
 package org.chromium.chrome.browser.customtabs;
 
 import android.app.Application;
+import android.graphics.Bitmap;
+import android.graphics.Rect;
 import android.os.SystemClock;
 import android.support.customtabs.CustomTabsCallback;
 import android.support.customtabs.CustomTabsSessionToken;
 
 import org.chromium.base.metrics.RecordHistogram;
+import org.chromium.chrome.R;
+import org.chromium.chrome.browser.prerender.ExternalPrerenderHandler;
 import org.chromium.chrome.browser.tab.EmptyTabObserver;
 import org.chromium.chrome.browser.tab.Tab;
 import org.chromium.chrome.browser.tab.TabObserver;
 import org.chromium.components.security_state.ConnectionSecurityLevel;
+import org.chromium.content_public.browser.ContentBitmapCallback;
 import org.chromium.content_public.browser.LoadUrlParams;
 
 import java.util.concurrent.TimeUnit;
@@ -25,6 +30,7 @@ class CustomTabObserver extends EmptyTabObserver {
     private final CustomTabsConnection mCustomTabsConnection;
     private final CustomTabsSessionToken mSession;
     private final boolean mOpenedByChrome;
+    private float mScaleForNavigationInfo = 1f;
 
     private long mIntentReceivedTimestamp;
     private long mPageLoadStartedTimestamp;
@@ -42,6 +48,15 @@ class CustomTabObserver extends EmptyTabObserver {
             mCustomTabsConnection = CustomTabsConnection.getInstance(application);
         }
         mSession = session;
+        if (!openedByChrome && mCustomTabsConnection.shouldSendNavigationInfoForSession(mSession)) {
+            float desiredWidth = application.getResources().getDimensionPixelSize(
+                    R.dimen.custom_tabs_screenshot_width);
+            float desiredHeight = application.getResources().getDimensionPixelSize(
+                    R.dimen.custom_tabs_screenshot_height);
+            Rect bounds = ExternalPrerenderHandler.estimateContentSize(application, false);
+            mScaleForNavigationInfo = (bounds.width() == 0 || bounds.height() == 0) ? 1f :
+                    Math.min(desiredWidth / bounds.width(), desiredHeight / bounds.height());
+        }
         mOpenedByChrome = openedByChrome;
         resetPageLoadTracking();
     }
@@ -113,6 +128,7 @@ class CustomTabObserver extends EmptyTabObserver {
                     TimeUnit.MILLISECONDS, 100);
         }
         resetPageLoadTracking();
+        captureNavigationInfo(tab);
     }
 
     @Override
@@ -138,4 +154,19 @@ class CustomTabObserver extends EmptyTabObserver {
         mCurrentState = STATE_RESET;
         mIntentReceivedTimestamp = -1;
     }
+
+    private void captureNavigationInfo(final Tab tab) {
+        if (mCustomTabsConnection == null) return;
+        if (!mCustomTabsConnection.shouldSendNavigationInfoForSession(mSession)) return;
+
+        ContentBitmapCallback callback = new ContentBitmapCallback() {
+            @Override
+            public void onFinishGetBitmap(Bitmap bitmap, int response) {
+                mCustomTabsConnection.sendNavigationInfo(
+                        mSession, tab.getUrl(), tab.getTitle(), bitmap);
+            }
+        };
+        tab.getWebContents().getContentBitmapAsync(
+                Bitmap.Config.ARGB_8888, mScaleForNavigationInfo, new Rect(), callback);
+    }
 }

chrome/android/java/src/org/chromium/chrome/browser/customtabs/CustomTabsConnection.java

@@ -480,6 +480,11 @@ public class CustomTabsConnection {
         return mClientManager.shouldPrerenderOnCellularForSession(session);
     }
 
+    /** @see ClientManager#shouldSendNavigationInfoForSession(CustomTabsSessionToken) */
+    public boolean shouldSendNavigationInfoForSession(CustomTabsSessionToken session) {
+        return mClientManager.shouldSendNavigationInfoForSession(session);
+    }
+
     /** See {@link ClientManager#getClientPackageNameForSession(CustomTabsSessionToken)} */
     public String getClientPackageNameForSession(CustomTabsSessionToken session) {
         return mClientManager.getClientPackageNameForSession(session);
@@ -523,6 +528,16 @@ public class CustomTabsConnection {
      */
     public void sendFirstRunCallbackIfNecessary(Intent intent, boolean resultOK) { }
 
+    /**
+     * Sends the navigation info that was captured to the client callback.
+     * @param session The session to use for getting client callback.
+     * @param url The current url for the tab.
+     * @param title The current title for the tab.
+     * @param screenshot A screenshot of the tab contents.
+     */
+    public void sendNavigationInfo(
+            CustomTabsSessionToken session, String url, String title, Bitmap screenshot) { }
+
     /**
      * Notifies the application of a navigation event.
      *