Bug 1419463 - Add onFocusRequest to ContentListener API. r=snorp

This listens for "DOMWindowFocus" and calls onFocusRequest in the GeckoSession ContentListener whenever it is received, and implements onFocusRequest for custom tabs and PWAs.

mobile/android/base/java/org/mozilla/gecko/GeckoApp.java

@@ -844,6 +844,10 @@ public abstract class GeckoApp extends GeckoActivity
     public void onTitleChange(final GeckoSession session, final String title) {
     }
 
+    @Override // GeckoSession.ContentListener
+    public void onFocusRequest(final GeckoSession session) {
+    }
+
     @Override // GeckoSession.ContentListener
     public void onFullScreen(final GeckoSession session, final boolean fullScreen) {
         if (fullScreen) {

mobile/android/base/java/org/mozilla/gecko/customtabs/CustomTabsActivity.java

@@ -678,6 +678,13 @@ public class CustomTabsActivity extends AppCompatActivity
         updateActionBar();
     }
 
+    @Override
+    public void onFocusRequest(GeckoSession session) {
+        Intent intent = new Intent(getIntent());
+        intent.addFlags(Intent.FLAG_ACTIVITY_REORDER_TO_FRONT);
+        startActivity(intent);
+    }
+
     @Override
     public void onFullScreen(GeckoSession session, boolean fullScreen) {
         ActivityUtils.setFullScreen(this, fullScreen);

mobile/android/base/java/org/mozilla/gecko/webapps/WebAppActivity.java

@@ -351,6 +351,13 @@ public class WebAppActivity extends AppCompatActivity
     public void onTitleChange(GeckoSession session, String title) {
     }
 
+    @Override // GeckoSession.ContentListener
+    public void onFocusRequest(GeckoSession session) {
+        Intent intent = new Intent(getIntent());
+        intent.addFlags(Intent.FLAG_ACTIVITY_REORDER_TO_FRONT);
+        startActivity(intent);
+    }
+
     @Override // GeckoSession.ContentListener
     public void onContextMenu(GeckoSession session, int screenX, int screenY,
                               String uri, String elementSrc) {

mobile/android/chrome/geckoview/GeckoViewContent.js

@@ -25,6 +25,7 @@ class GeckoViewContent extends GeckoViewContentModule {
     debug("register");
 
     addEventListener("DOMTitleChanged", this, false);
+    addEventListener("DOMWindowFocus", this, false);
     addEventListener("MozDOMFullscreen:Entered", this, false);
     addEventListener("MozDOMFullscreen:Exit", this, false);
     addEventListener("MozDOMFullscreen:Exited", this, false);
@@ -43,6 +44,7 @@ class GeckoViewContent extends GeckoViewContentModule {
     debug("unregister");
 
     removeEventListener("DOMTitleChanged", this);
+    removeEventListener("DOMWindowFocus", this);
     removeEventListener("MozDOMFullscreen:Entered", this);
     removeEventListener("MozDOMFullscreen:Exit", this);
     removeEventListener("MozDOMFullscreen:Exited", this);
@@ -173,6 +175,11 @@ class GeckoViewContent extends GeckoViewContentModule {
           title: content.document.title
         });
         break;
+      case "DOMWindowFocus":
+        this.eventDispatcher.sendRequest({
+          type: "GeckoView:DOMWindowFocus"
+        });
+        break;
     }
   }
 }

mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoSession.java

@@ -75,6 +75,7 @@ public class GeckoSession extends LayerSession
             new String[]{
                 "GeckoView:ContextMenu",
                 "GeckoView:DOMTitleChanged",
+                "GeckoView:DOMWindowFocus",
                 "GeckoView:FullScreenEnter",
                 "GeckoView:FullScreenExit"
             }
@@ -94,6 +95,8 @@ public class GeckoSession extends LayerSession
                 } else if ("GeckoView:DOMTitleChanged".equals(event)) {
                     listener.onTitleChange(GeckoSession.this,
                                            message.getString("title"));
+                } else if ("GeckoView:DOMWindowFocus".equals(event)) {
+                    listener.onFocusRequest(GeckoSession.this);
                 } else if ("GeckoView:FullScreenEnter".equals(event)) {
                     listener.onFullScreen(GeckoSession.this, true);
                 } else if ("GeckoView:FullScreenExit".equals(event)) {
@@ -1197,6 +1200,13 @@ public class GeckoSession extends LayerSession
         */
         void onTitleChange(GeckoSession session, String title);
 
+        /**
+        * A page has requested focus. Note that window.focus() in content will not result
+        * in this being called.
+        * @param session The GeckoSession that initiated the callback.
+        */
+        void onFocusRequest(GeckoSession session);
+
         /**
          * A page has entered or exited full screen mode. Typically, the implementation
          * would set the Activity containing the GeckoSession to full screen when the page is

mobile/android/geckoview_example/src/main/java/org/mozilla/geckoview_example/GeckoViewActivity.java

@@ -162,6 +162,11 @@ public class GeckoViewActivity extends Activity {
             Log.i(LOGTAG, "Content title changed to " + title);
         }
 
+        @Override
+        public void onFocusRequest(GeckoSession session) {
+            Log.i(LOGTAG, "Content requesting focus");
+        }
+
         @Override
         public void onFullScreen(final GeckoSession session, final boolean fullScreen) {
             getWindow().setFlags(fullScreen ? WindowManager.LayoutParams.FLAG_FULLSCREEN : 0,