Add overscroll edge effect animations for Android.

content/browser/renderer_host/render_widget_host_view_android.cc

Index: content/browser/renderer_host/render_widget_host_view_android.cc
diff --git a/content/browser/renderer_host/render_widget_host_view_android.cc b/content/browser/renderer_host/render_widget_host_view_android.cc
index 871f1f2819761863c55c4760ef1c4cde55bbcd4e..b36c44179024ca170f0da1e13ab2f7cd73fe4dd2 100644
--- a/content/browser/renderer_host/render_widget_host_view_android.cc
+++ b/content/browser/renderer_host/render_widget_host_view_android.cc
@@ -7,6 +7,7 @@
 #include <android/bitmap.h>
 
 #include "base/bind.h"
+#include "base/command_line.h"
 #include "base/logging.h"
 #include "base/message_loop.h"
 #include "base/utf_string_conversions.h"
@@ -15,6 +16,7 @@
 #include "cc/output/compositor_frame.h"
 #include "cc/output/compositor_frame_ack.h"
 #include "content/browser/android/content_view_core_impl.h"
+#include "content/browser/android/overscroll_glow.h"
 #include "content/browser/gpu/gpu_surface_tracker.h"
 #include "content/browser/renderer_host/compositor_impl_android.h"
 #include "content/browser/renderer_host/image_transport_factory_android.h"
@@ -23,6 +25,7 @@
 #include "content/common/gpu/client/gl_helper.h"
 #include "content/common/gpu/gpu_messages.h"
 #include "content/common/view_messages.h"
+#include "content/public/common/content_switches.h"
 #include "third_party/WebKit/Source/Platform/chromium/public/Platform.h"
 #include "third_party/WebKit/Source/Platform/chromium/public/WebExternalTextureLayer.h"
 #include "third_party/WebKit/Source/Platform/chromium/public/WebSize.h"
@@ -73,12 +76,15 @@ RenderWidgetHostViewAndroid::RenderWidgetHostViewAndroid(
     RenderWidgetHostImpl* widget_host,
     ContentViewCoreImpl* content_view_core)
     : host_(widget_host),
-      is_layer_attached_(true),
+      are_layers_attached_(true),
       content_view_core_(NULL),
       ime_adapter_android_(ALLOW_THIS_IN_INITIALIZER_LIST(this)),
       cached_background_color_(SK_ColorWHITE),
       texture_id_in_layer_(0),
-      consumed_current_texture_(true) {
+      consumed_current_texture_(true),
+      vsync_notifications_enabled_(false),
+      animation_vsync_notifications_enabled_(false),
+      renderer_vsync_notifications_enabled_(false) {
   if (CompositorImpl::UsesDirectGL()) {
     surface_texture_transport_.reset(new SurfaceTextureTransportClient());
     layer_ = surface_texture_transport_->Initialize();
@@ -90,6 +96,11 @@ RenderWidgetHostViewAndroid::RenderWidgetHostViewAndroid(
 
   layer_->SetContentsOpaque(true);
 
+  if (CommandLine::ForCurrentProcess()->
+          HasSwitch(switches::kEnableOverscrollEdgeEffect)) {
+    overscroll_effect_ = OverscrollGlow::Create();
+  }
+
   host_->SetView(this);
   SetContentViewCore(content_view_core);
 }
@@ -283,6 +294,9 @@ void RenderWidgetHostViewAndroid::Blur() {
       host_->GetRoutingID(), "Unselect", ""));
   host_->SetInputMethodActive(false);
   host_->Blur();
+
+  if (overscroll_effect_)
+    overscroll_effect_->Finish();
 }
 
 bool RenderWidgetHostViewAndroid::HasFocus() const {
@@ -298,28 +312,26 @@ bool RenderWidgetHostViewAndroid::IsSurfaceAvailableForCopy() const {
 }
 
 void RenderWidgetHostViewAndroid::Show() {
-  if (is_layer_attached_)
+  if (are_layers_attached_)
     return;
 
-  is_layer_attached_ = true;
-  if (content_view_core_)
-    content_view_core_->AttachLayer(layer_);
+  are_layers_attached_ = true;
+  AttachLayers();
 }
 
 void RenderWidgetHostViewAndroid::Hide() {
-  if (!is_layer_attached_)
+  if (!are_layers_attached_)
     return;
 
-  is_layer_attached_ = false;
-  if (content_view_core_)
-    content_view_core_->RemoveLayer(layer_);
+  are_layers_attached_ = false;
+  RemoveLayers();
 }
 
 bool RenderWidgetHostViewAndroid::IsShowing() {
   // ContentViewCoreImpl represents the native side of the Java
   // ContentViewCore.  It being NULL means that it is not attached
   // to the View system yet, so we treat this RWHVA as hidden.
-  return is_layer_attached_ && content_view_core_;
+  return are_layers_attached_ && content_view_core_;
 }
 
 gfx::Rect RenderWidgetHostViewAndroid::GetViewBounds() const {
@@ -395,12 +407,25 @@ void RenderWidgetHostViewAndroid::OnDidChangeBodyBackgroundColor(
 }
 
 void RenderWidgetHostViewAndroid::SendVSync(base::TimeTicks frame_time) {
-  host_->Send(new ViewMsg_DidVSync(host_->GetRoutingID(), frame_time));
+  if (renderer_vsync_notifications_enabled_)
+    host_->Send(new ViewMsg_DidVSync(host_->GetRoutingID(), frame_time));
+  if (animation_vsync_notifications_enabled_)
+    Animate();
 }
 
 void RenderWidgetHostViewAndroid::OnSetVSyncNotificationEnabled(bool enabled) {
-  if (content_view_core_)
-    content_view_core_->SetVSyncNotificationEnabled(enabled);
+  renderer_vsync_notifications_enabled_ = enabled;
+  RequestVSyncNotificationsIfNecessary();
+}
+
+void RenderWidgetHostViewAndroid::RequestVSyncNotificationsIfNecessary() {
+  bool notifications_enabled = animation_vsync_notifications_enabled_ ||
+                               renderer_vsync_notifications_enabled_;
+  if (notifications_enabled != vsync_notifications_enabled_) {
+    if (content_view_core_)
+      content_view_core_->SetVSyncNotificationEnabled(notifications_enabled);
+    vsync_notifications_enabled_ = notifications_enabled;
+  }
 }
 
 void RenderWidgetHostViewAndroid::OnStartContentIntent(
@@ -431,10 +456,8 @@ void RenderWidgetHostViewAndroid::RenderViewGone(
 }
 
 void RenderWidgetHostViewAndroid::Destroy() {
-  if (content_view_core_) {
-    content_view_core_->RemoveLayer(layer_);
-    content_view_core_ = NULL;
-  }
+  RemoveLayers();
+  content_view_core_ = NULL;
 
   // The RenderWidgetHost's destruction led here, so don't call it.
   host_ = NULL;
@@ -565,6 +588,15 @@ void RenderWidgetHostViewAndroid::OnSwapCompositorFrame(
                  content_size,
                  callback);
 
+  if (overscroll_effect_) {
+    // Disable edge effects for axes on which scrolling is impossible.
+    const cc::CompositorFrameMetadata& metadata = frame->metadata;
+    overscroll_effect_->set_horizontal_overscroll_enabled(
+        metadata.root_layer_size.width() != metadata.viewport_size.width());
+    overscroll_effect_->set_vertical_overscroll_enabled(
+        metadata.root_layer_size.height() != metadata.viewport_size.height());
+    overscroll_effect_->set_size(content_size);
+  }
 }
 
 void RenderWidgetHostViewAndroid::AcceleratedSurfaceBuffersSwapped(
@@ -642,6 +674,40 @@ void RenderWidgetHostViewAndroid::BuffersSwapped(
   consumed_current_texture_ = false;
 }
 
+void RenderWidgetHostViewAndroid::AttachLayers() {
+  if (!content_view_core_)
+    return;
+
+  content_view_core_->AttachLayer(layer_);
+
+  if (overscroll_effect_)
+    overscroll_effect_->set_parent_layer(content_view_core_->GetLayer());
+}
+
+void RenderWidgetHostViewAndroid::RemoveLayers() {
+  if (!content_view_core_)
+    return;
+
+  if (overscroll_effect_)
+    overscroll_effect_->set_parent_layer(NULL);
+
+  content_view_core_->RemoveLayer(layer_);
+}
+
+void RenderWidgetHostViewAndroid::Animate() {
+  if (!overscroll_effect_)
+   return;
+  overscroll_effect_->Animate(base::TimeTicks::Now());
+  ScheduleAnimation();
+}
+
+void RenderWidgetHostViewAndroid::ScheduleAnimation() {
+  animation_vsync_notifications_enabled_ = overscroll_effect_ &&
+                                           overscroll_effect_->IsAnimating() &&
+                                           HasFocus();
+  RequestVSyncNotificationsIfNecessary();
+}
+
 void RenderWidgetHostViewAndroid::AcceleratedSurfacePostSubBuffer(
     const GpuHostMsg_AcceleratedSurfacePostSubBuffer_Params& params,
     int gpu_host_id) {
@@ -780,16 +846,28 @@ SkColor RenderWidgetHostViewAndroid::GetCachedBackgroundColor() const {
   return cached_background_color_;
 }
 
+void RenderWidgetHostViewAndroid::OnOverscrolled(
+    const gfx::Vector2dF& accumulated_overscroll,
+    const gfx::Vector2dF& current_fling_velocity) {
+  if (overscroll_effect_) {
+    overscroll_effect_->OnOverscrolled(base::TimeTicks::Now(),
+                                       accumulated_overscroll,
+                                       current_fling_velocity);
+    ScheduleAnimation();
+  }
+}
+
 void RenderWidgetHostViewAndroid::SetContentViewCore(
     ContentViewCoreImpl* content_view_core) {
   RunAckCallbacks();
 
-  if (content_view_core_ && is_layer_attached_)
-    content_view_core_->RemoveLayer(layer_);
+  if (are_layers_attached_)
+    RemoveLayers();
 
   content_view_core_ = content_view_core;
-  if (content_view_core_ && is_layer_attached_)
-    content_view_core_->AttachLayer(layer_);
+
+  if (are_layers_attached_)
+    AttachLayers();
 }
 
 void RenderWidgetHostViewAndroid::RunAckCallbacks() {