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 1597e00b40a6faf85ce01de466303f514f2d404c..7ba2f80504313961ad9464aba0313907cc6af20e 100644
--- a/content/browser/renderer_host/render_widget_host_view_android.cc
+++ b/content/browser/renderer_host/render_widget_host_view_android.cc
@@ -15,6 +15,7 @@
 #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"
@@ -67,17 +68,30 @@ void InsertSyncPointAndAckForCompositor(
       route_id, renderer_host_id, ack);
 }
 
+scoped_ptr<OverscrollGlow> CreateOverscrollEffect(
+    ContentViewCoreImpl* content_view_core){
+  if (content_view_core != NULL &&
+      !content_view_core->get_overscroll_edge().isNull() &&
+      !content_view_core->get_overscroll_glow().isNull()) {
+    return make_scoped_ptr(
+        new OverscrollGlow(content_view_core->get_overscroll_edge(),
+                           content_view_core->get_overscroll_glow()));
+  }
+  return scoped_ptr<OverscrollGlow>();
+}
+
 }  // anonymous namespace
 
 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) {
+      texture_id_in_layer_(0),
+      overscroll_resources_updated_(true) {
   if (CompositorImpl::UsesDirectGL()) {
     surface_texture_transport_.reset(new SurfaceTextureTransportClient());
     layer_ = surface_texture_transport_->Initialize();
@@ -289,28 +303,26 @@ 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 {
@@ -391,6 +403,10 @@ void RenderWidgetHostViewAndroid::OnStartContentIntent(
     content_view_core_->StartContentIntent(content_url);
 }
 
+void RenderWidgetHostViewAndroid::OnSetOverscrollResources() {
+  overscroll_resources_updated_ = true;
+}
+
 void RenderWidgetHostViewAndroid::ImeCancelComposition() {
   ime_adapter_android_.CancelComposition();
 }
@@ -413,10 +429,10 @@ void RenderWidgetHostViewAndroid::RenderViewGone(
 }
 
 void RenderWidgetHostViewAndroid::Destroy() {
-  if (content_view_core_) {
-    content_view_core_->RemoveLayer(layer_);
-    content_view_core_ = NULL;
-  }
+  RemoveLayers();
+  content_view_core_ = NULL;
+
+  overscroll_effect_.reset();
 
   // The RenderWidgetHost's destruction led here, so don't call it.
   host_ = NULL;
@@ -595,6 +611,13 @@ void RenderWidgetHostViewAndroid::BuffersSwapped(
   texture_layer_->SetBounds(gfx::Size(content_size.width(),
                                       content_size.height()));
 
+  if (overscroll_resources_updated_) {
+    SetOverscrollEffect(CreateOverscrollEffect(content_view_core_));
+    overscroll_resources_updated_ = false;
+  }
+  if (overscroll_effect_)
+    overscroll_effect_->set_size(content_size);
+
   // Calculate the uv_max based on the content size relative to the texture
   // size.
   gfx::PointF uv_max;
@@ -608,6 +631,50 @@ void RenderWidgetHostViewAndroid::BuffersSwapped(
   ack_callback.Run();
 }
 
+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::SetOverscrollEffect(
+    scoped_ptr<OverscrollGlow> overscroll_effect) {
+  animation_timer_.Stop();
+  overscroll_effect_.swap(overscroll_effect);
+  if (content_view_core_ && are_layers_attached_)
+    overscroll_effect_->set_parent_layer(content_view_core_->GetLayer());
+}
+
+void RenderWidgetHostViewAndroid::AnimationCallback() {
+  if (overscroll_effect_ && overscroll_effect_->Animate(base::TimeTicks::Now()))
+    AnimateIfNeeded();
+}
+
+void RenderWidgetHostViewAndroid::AnimateIfNeeded() {
+  if (animation_timer_.IsRunning() || !overscroll_effect_)
+    return;
+
+  const base::TimeDelta animationInterval
+      = base::TimeDelta::FromMilliseconds(kDesiredAnimationIntervalInMs);
+
+  animation_timer_.Start(FROM_HERE, animationInterval, this,
+                         &RenderWidgetHostViewAndroid::AnimationCallback);
+}
+
 void RenderWidgetHostViewAndroid::AcceleratedSurfacePostSubBuffer(
     const GpuHostMsg_AcceleratedSurfacePostSubBuffer_Params& params,
     int gpu_host_id) {
@@ -761,16 +828,32 @@ void RenderWidgetHostViewAndroid::UpdateFrameInfo(
         content_size, viewport_size, controls_offset, content_offset,
         overdraw_bottom_height);
   }
+
+  if (overscroll_effect_)
+    overscroll_effect_->set_horizontal_overscroll_enabled(
+        content_size.width() != viewport_size.width());
+
+}
+
+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);
+    AnimateIfNeeded();
+  }
 }
 
 void RenderWidgetHostViewAndroid::SetContentViewCore(
     ContentViewCoreImpl* content_view_core) {
-  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::HasTouchEventHandlers(