DO NOT COMMIT - DialogSurface initial implementation.

content/public/android/java/src/org/chromium/content/browser/DialogSurfaceActivityMapper.java

Index: content/public/android/java/src/org/chromium/content/browser/DialogSurfaceActivityMapper.java
diff --git a/content/public/android/java/src/org/chromium/content/browser/DialogSurfaceActivityMapper.java b/content/public/android/java/src/org/chromium/content/browser/DialogSurfaceActivityMapper.java
new file mode 100644
index 0000000000000000000000000000000000000000..e526f263f51bf626dba1966deda37eb622ebeb6a
--- /dev/null
+++ b/content/public/android/java/src/org/chromium/content/browser/DialogSurfaceActivityMapper.java
@@ -0,0 +1,44 @@
+// Copyright 2016 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.content.browser;
+
+import android.app.Activity;
+import android.os.IBinder;
+
+import org.chromium.media.IDialogSurfaceActivityMapper;
+
+/**
+ * Implementation of IDialogSurfaceActivityMapper.
+ * Provided by ChildProcessLauncher to DialogSurfaceManager.
+ */
+public class DialogSurfaceActivityMapper extends IDialogSurfaceActivityMapper.Stub {
+    /**
+     * Return a window token for the (rendererPid, renderFrameId) pair.
+     * @param rendererPid the PID of the renderer that we're looking up.
+     * @param renderFrameId the ID of the render frame within that PID.
+     */
+    public IBinder getWindowToken(int rendererPid, int renderFrameId) {
+        final Activity activity = getActivity(rendererPid, renderFrameId);
+        if (activity == null) return null;
+
+        return activity.getWindow().getDecorView().getRootView().getWindowToken();
+    }
+
+    /**
+     * Return the activity for (rendererPid, renderFrameId), or null.
+     * @param rendererPid the PID of the renderer that we're looking up.
+     * @param renderFrameId the ID of the render frame within that PID.
+     */
+    private Activity getActivity(int rendererPid, int renderFrameId) {
+        ContentViewCore cvc = nativeGetContentViewCore(rendererPid, renderFrameId);
+        if (cvc == null) return null;
+
+        // Note that this weakref's referent can be null for webview.
+        return cvc.getWindowAndroid().getActivity().get();
+    }
+
+    private static native ContentViewCore nativeGetContentViewCore(
+            int renderPid, int renderFrameId);
+}