Add tab reparenting

content/browser/renderer_host/render_widget_host_view_android.cc

 // Copyright (c) 2012 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.
 
 #include "content/browser/renderer_host/render_widget_host_view_android.h"
 
 #include <android/bitmap.h>
 #include <utility>
 
 #include "base/android/build_info.h"
@@ skipping 1741 matching lines @@
          (content_view_core_ == content_view_core));
   RemoveLayers();
   StopObservingRootWindow();
 
   bool resize = false;
   if (content_view_core != content_view_core_) {
     overscroll_controller_.reset();
     selection_controller_.reset();
     ReleaseLocksOnSurface();
     resize = true;
-    if (content_view_core_) {
-      if (!content_view_core)
-        content_view_core_->RemoveObserver(this);
-      else
-        content_view_core->AddObserver(this);
-    }
+    if (content_view_core_ && !content_view_core)
+      content_view_core_->RemoveObserver(this);

[no sievers, 2016/02/25 19:23:16]

So that fixes the else-path where we might not have attached to the new CVC
previously if |content_view_core_| was null.

But also: why do we want to stay attached to |content_view_core_| if
|content_view_core| is not null?

[Yusuf, 2016/02/25 19:37:03]

Another good point. Right now, we never call a single widget with multiple CVCs
I believe. That is why I didn't add it. Added a condition for it as well just in
case.

+    else
+      content_view_core->AddObserver(this);
   }
 
   content_view_core_ = content_view_core;
 
   BrowserAccessibilityManager* manager = NULL;
   if (host_)
     manager = host_->GetRootBrowserAccessibilityManager();
   if (manager) {
     base::android::ScopedJavaLocalRef<jobject> obj;
     if (content_view_core_)
@@ skipping 268 matching lines @@
   results->orientationAngle = display.RotationAsDegree();
   results->orientationType =
       RenderWidgetHostViewBase::GetOrientationTypeForMobile(display);
   gfx::DeviceDisplayInfo info;
   results->depth = info.GetBitsPerPixel();
   results->depthPerComponent = info.GetBitsPerComponent();
   results->isMonochrome = (results->depthPerComponent == 0);
 }
 
 }  // namespace content