Delegate root layer scroll offset to android_webview.

content/browser/android/in_process/synchronous_compositor_impl.cc

 // Copyright 2013 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/android/in_process/synchronous_compositor_impl.h"
 
 #include "base/lazy_instance.h"
 #include "base/message_loop.h"
+#include "cc/input/input_handler.h"
+#include "cc/input/layer_scroll_offset_delegate.h"
 #include "content/browser/android/in_process/synchronous_input_event_filter.h"
 #include "content/public/browser/android/synchronous_compositor_client.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/render_process_host.h"
 #include "content/public/browser/render_view_host.h"
 #include "content/renderer/android/synchronous_compositor_factory.h"
 #include "webkit/common/gpu/context_provider_in_process.h"
 
 namespace content {
 
@@ skipping 85 matching lines @@
 }
 
 SynchronousCompositorImpl* SynchronousCompositorImpl::FromRoutingID(
     int routing_id) {
   return FromID(GetInProcessRendererId(), routing_id);
 }
 
 SynchronousCompositorImpl::SynchronousCompositorImpl(WebContents* contents)
     : compositor_client_(NULL),
       output_surface_(NULL),
-      contents_(contents) {
+      contents_(contents),
+      input_handler_(NULL) {
   DCHECK(contents);
 }
 
 SynchronousCompositorImpl::~SynchronousCompositorImpl() {
   if (compositor_client_)
     compositor_client_->DidDestroyCompositor(this);
 }
 
 void SynchronousCompositorImpl::SetClient(
     SynchronousCompositorClient* compositor_client) {
@@ skipping 17 matching lines @@
   return output_surface_->DemandDrawHw(view_size, transform, damage_area);
 }
 
 bool SynchronousCompositorImpl::DemandDrawSw(SkCanvas* canvas) {
   DCHECK(CalledOnValidThread());
   DCHECK(output_surface_);
 
   return output_surface_->DemandDrawSw(canvas);
 }
 
+void SynchronousCompositorImpl::DidChangeRootLayerScrollOffset() {
+  if (input_handler_)
+    input_handler_->OnRootLayerDelegatedScrollOffsetChanged();
+}
+
 void SynchronousCompositorImpl::DidBindOutputSurface(
       SynchronousCompositorOutputSurface* output_surface) {
   DCHECK(CalledOnValidThread());
   output_surface_ = output_surface;
   if (compositor_client_)
     compositor_client_->DidInitializeCompositor(this);
 }
 
 void SynchronousCompositorImpl::DidDestroySynchronousOutputSurface(
        SynchronousCompositorOutputSurface* output_surface) {
   DCHECK(CalledOnValidThread());
+
   // Allow for transient hand-over when two output surfaces may refer to
   // a single delegate.
   if (output_surface_ == output_surface) {
     output_surface_ = NULL;
     if (compositor_client_)
       compositor_client_->DidDestroyCompositor(this);
     compositor_client_ = NULL;
   }
 }
 
+void SynchronousCompositorImpl::SetInputHandler(
+    cc::InputHandler* input_handler) {
+  DCHECK(CalledOnValidThread());
+
+  if (input_handler_)
+    input_handler_->SetRootLayerScrollOffsetDelegate(NULL);
+
+  input_handler_ = input_handler;
+
+  if (input_handler_)
+    input_handler_->SetRootLayerScrollOffsetDelegate(this);
+}
+
 void SynchronousCompositorImpl::SetContinuousInvalidate(bool enable) {
   DCHECK(CalledOnValidThread());
   if (compositor_client_)
     compositor_client_->SetContinuousInvalidate(enable);
 }
 
 InputEventAckState SynchronousCompositorImpl::HandleInputEvent(
     const WebKit::WebInputEvent& input_event) {
   DCHECK(CalledOnValidThread());
   return g_factory.Get().synchronous_input_event_filter()->HandleInputEvent(
       contents_->GetRoutingID(), input_event);
 }
 
+void SynchronousCompositorImpl::SetTotalScrollOffset(gfx::Vector2dF new_value) {
+  DCHECK(CalledOnValidThread());
+  if (compositor_client_)
+    compositor_client_->SetTotalRootLayerScrollOffset(new_value);
+}
+
+gfx::Vector2dF SynchronousCompositorImpl::GetTotalScrollOffset() {
+  DCHECK(CalledOnValidThread());
+  if (compositor_client_)
+    return compositor_client_->GetTotalRootLayerScrollOffset();
+  return gfx::Vector2dF();
+}
+
 // Not using base::NonThreadSafe as we want to enforce a more exacting threading
 // requirement: SynchronousCompositorImpl() must only be used on the UI thread.
 bool SynchronousCompositorImpl::CalledOnValidThread() const {
   return BrowserThread::CurrentlyOn(BrowserThread::UI);
 }
 
 // static
 void SynchronousCompositor::SetClientForWebContents(
     WebContents* contents,
     SynchronousCompositorClient* client) {
   DCHECK(contents);
   if (client) {
     g_factory.Get();  // Ensure it's initialized.
     SynchronousCompositorImpl::CreateForWebContents(contents);
   }
   if (SynchronousCompositorImpl* instance =
       SynchronousCompositorImpl::FromWebContents(contents)) {
     instance->SetClient(client);
   }
 }
 
 }  // namespace content