AW: Expose WebView developer UI in WebView shell browser menu

Add menu option in WebView shell browser to launch developer UI from the
current WebView package.

Add intent-filter to WebView developer UI MainActivity with a new action
"com.android.webview.SHOW_DEV_UI".

Fixed: 1014827
Test: Manually inspect and launch dev ui from shell browser menu
Test: Build and install SystemWebView and Monochrome switch providers and verify the right UI is launched
Test: Build and install tip-of-the-tree SystemWebView and verify that a failure toast is shown
Change-Id: Ia00ae05118e2974ac1e6ddd3b95c70717da862a2
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1893864
Auto-Submit: Hazem Ashmawy <hazems@chromium.org>
Reviewed-by: Richard Coles <torne@chromium.org>
Reviewed-by: Andrew Grieve <agrieve@chromium.org>
Reviewed-by: Nate Fischer <ntfschr@chromium.org>
Commit-Queue: Hazem Ashmawy <hazems@chromium.org>
Cr-Commit-Position: refs/heads/master@{#712313}

android_webview/apk/java/AndroidManifest.xml

@@ -36,6 +36,10 @@
                       android:theme="@android:style/Theme.DeviceDefault"
                       android:launchMode="singleTask"
                       android:process=":webview_apk">  {# Explicit process required for monochrome compatibility. #}
+                <intent-filter>
+                    <action android:name="com.android.webview.SHOW_DEV_UI" />
+                    <category android:name="android.intent.category.DEFAULT" />
+                </intent-filter>
             </activity>
             <activity android:name="org.chromium.android_webview.devui.CrashesListActivity"
                       android:label="WebView Crashes"

android_webview/tools/system_webview_shell/BUILD.gn

@@ -29,6 +29,7 @@ android_apk("system_webview_shell_apk") {
     "apk/src/org/chromium/webview_shell/WebViewBrowserActivity.java",
     "apk/src/org/chromium/webview_shell/WebViewCreateDestroyActivity.java",
     "apk/src/org/chromium/webview_shell/WebViewLayoutTestActivity.java",
+    "apk/src/org/chromium/webview_shell/WebViewPackageHelper.java",
     "apk/src/org/chromium/webview_shell/WebViewThreadTestActivity.java",
     "apk/src/org/chromium/webview_shell/WebViewTracingActivity.java",
   ]

android_webview/tools/system_webview_shell/apk/res/menu/main_menu.xml

@@ -17,4 +17,6 @@
           android:title="@string/menu_start_animation_activity"/>
     <item android:id="@+id/menu_about"
           android:title="@string/menu_about"/>
+    <item android:id="@+id/menu_devui"
+          android:title="@string/menu_devui"/>
 </menu>

android_webview/tools/system_webview_shell/apk/res/values/strings.xml

@@ -20,6 +20,7 @@
     <string name="menu_start_animation_activity">Animation test</string>
     <string name="menu_print">Print</string>
     <string name="menu_about">About WebView</string>
+    <string name="menu_devui">WebView DevTools</string>
     <string name="load_url">Load URL</string>
 
     <!-- activity_webview_animation_test strings -->

android_webview/tools/system_webview_shell/apk/src/org/chromium/webview_shell/WebViewBrowserActivity.java

@@ -13,6 +13,7 @@ import android.content.ActivityNotFoundException;
 import android.content.Context;
 import android.content.Intent;
 import android.content.IntentFilter;
+import android.content.pm.PackageInfo;
 import android.content.pm.PackageManager;
 import android.content.pm.ResolveInfo;
 import android.graphics.Bitmap;
@@ -579,6 +580,9 @@ public class WebViewBrowserActivity extends AppCompatActivity {
                 about();
                 hideKeyboard(mUrlBar);
                 return true;
+            case R.id.menu_devui:
+                launchWebViewDevUI();
+                return true;
             default:
                 break;
         }
@@ -635,6 +639,31 @@ public class WebViewBrowserActivity extends AppCompatActivity {
         dialog.getWindow().setLayout(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);
     }
 
+    private void launchWebViewDevUI() {
+        PackageInfo currentWebViewPackage = WebViewPackageHelper.getCurrentWebViewPackage(this);
+        if (currentWebViewPackage == null) {
+            Log.e(TAG, "Couldn't find current WebView package");
+            Toast.makeText(this, "WebView package isn't found", Toast.LENGTH_LONG).show();
+            return;
+        }
+        String currentWebViewPackageName = currentWebViewPackage.packageName;
+        Intent intent = new Intent("com.android.webview.SHOW_DEV_UI");
+        intent.setPackage(currentWebViewPackageName);
+
+        // Check if the intent is resolved, i.e current WebView package has a developer UI that
+        // responds to "com.android.webview.SHOW_DEV_UI" action.
+        List<ResolveInfo> intentResolveInfo = getPackageManager().queryIntentActivities(intent, 0);
+        if (intentResolveInfo.size() > 0) {
+            startActivity(intent);
+        } else {
+            Log.e(TAG,
+                    "Couldn't launch developer UI from current WebView package: "
+                            + currentWebViewPackage);
+            Toast.makeText(this, "No DevTools in " + currentWebViewPackageName, Toast.LENGTH_LONG)
+                    .show();
+        }
+    }
+
     // Returns true is a method has no arguments and returns either a boolean or a String.
     private boolean methodIsSimpleInspector(Method method) {
         Class<?> returnType = method.getReturnType();

android_webview/tools/system_webview_shell/apk/src/org/chromium/webview_shell/WebViewPackageHelper.java

+// Copyright 2019 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.webview_shell;
+
+import android.annotation.SuppressLint;
+import android.content.Context;
+import android.content.pm.PackageInfo;
+import android.content.pm.PackageManager;
+import android.os.Build;
+import android.webkit.WebView;
+
+import java.lang.reflect.InvocationTargetException;
+
+/**
+ * A helper class to get info about WebView package.
+ */
+// TODO(crbug.com/1020024) use androidx.webkit.WebViewCompat#getCurrentWebViewPackage and remove
+// this class.
+public final class WebViewPackageHelper {
+    /**
+     * If WebView has already been loaded into the current process this method will return the
+     * package that was used to load it. Otherwise, the package that would be used if the WebView
+     * was loaded right now will be returned; this does not cause WebView to be loaded, so this
+     * information may become outdated at any time.
+     * The WebView package changes either when the current WebView package is updated, disabled, or
+     * uninstalled. It can also be changed through a Developer Setting.
+     * If the WebView package changes, any app process that has loaded WebView will be killed. The
+     * next time the app starts and loads WebView it will use the new WebView package instead.
+     * @return the current WebView package, or {@code null} if there is none.
+     */
+    // This method is copied from androidx.webkit.WebViewCompat.
+    public static PackageInfo getCurrentWebViewPackage(Context context) {
+        // There was no WebView Package before Lollipop, the WebView code was part of the framework
+        // back then.
+        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.LOLLIPOP) {
+            return null;
+        }
+
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
+            return WebView.getCurrentWebViewPackage();
+        } else { // L-N
+            try {
+                PackageInfo loadedWebViewPackageInfo = getLoadedWebViewPackageInfo();
+                if (loadedWebViewPackageInfo != null) return loadedWebViewPackageInfo;
+            } catch (ClassNotFoundException | IllegalAccessException | InvocationTargetException
+                    | NoSuchMethodException e) {
+                return null;
+            }
+
+            // If WebViewFactory.getLoadedPackageInfo() returns null then WebView hasn't been loaded
+            // yet, in that case we need to fetch the name of the WebView package, and fetch the
+            // corresponding PackageInfo through the PackageManager
+            return getNotYetLoadedWebViewPackageInfo(context);
+        }
+    }
+
+    /**
+     * Return the PackageInfo of the currently loaded WebView APK. This method uses reflection and
+     * propagates any exceptions thrown, to the caller.
+     */
+    // This method is copied from androidx.webkit.WebViewCompat.
+    @SuppressLint("PrivateApi")
+    private static PackageInfo getLoadedWebViewPackageInfo()
+            throws ClassNotFoundException, NoSuchMethodException, InvocationTargetException,
+                   IllegalAccessException {
+        Class<?> webViewFactoryClass = Class.forName("android.webkit.WebViewFactory");
+        return (PackageInfo) webViewFactoryClass.getMethod("getLoadedPackageInfo").invoke(null);
+    }
+
+    /**
+     * Return the PackageInfo of the WebView APK that would have been used as WebView implementation
+     * if WebView was to be loaded right now.
+     */
+    // This method is copied from androidx.webkit.WebViewCompat.
+    @SuppressLint("PrivateApi")
+    private static PackageInfo getNotYetLoadedWebViewPackageInfo(Context context) {
+        String webviewPackageName;
+        try {
+            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP
+                    && Build.VERSION.SDK_INT <= Build.VERSION_CODES.M) {
+                Class<?> webViewFactoryClass = Class.forName("android.webkit.WebViewFactory");
+
+                webviewPackageName = (String) webViewFactoryClass.getMethod("getWebViewPackageName")
+                                             .invoke(null);
+            } else {
+                Class<?> webviewUpdateServiceClass =
+                        Class.forName("android.webkit.WebViewUpdateService");
+                webviewPackageName =
+                        (String) webviewUpdateServiceClass.getMethod("getCurrentWebViewPackageName")
+                                .invoke(null);
+            }
+        } catch (ClassNotFoundException e) {
+            return null;
+        } catch (IllegalAccessException e) {
+            return null;
+        } catch (InvocationTargetException e) {
+            return null;
+        } catch (NoSuchMethodException e) {
+            return null;
+        }
+        if (webviewPackageName == null) return null;
+        PackageManager pm = context.getPackageManager();
+        try {
+            return pm.getPackageInfo(webviewPackageName, 0);
+        } catch (PackageManager.NameNotFoundException e) {
+            return null;
+        }
+    }
+
+    // Do not instantiate this class.
+    private WebViewPackageHelper() {}
+}

chrome/android/java/monochrome_public_bundle__base_bundle_module.AndroidManifest.expected

@@ -1018,7 +1018,12 @@
         android:launchMode="singleTask"
         android:name="org.chromium.android_webview.devui.MainActivity"
         android:process=":webview_apk"
-        android:theme="@android:style/Theme.DeviceDefault"/>
+        android:theme="@android:style/Theme.DeviceDefault">
+      <intent-filter>
+        <action android:name="com.android.webview.SHOW_DEV_UI"/>
+        <category android:name="android.intent.category.DEFAULT"/>
+      </intent-filter>
+    </activity>
     <activity
         android:enabled="false"
         android:excludeFromRecents="true"