Unified BeginFrame scheduling

content/browser/renderer_host/render_widget_host_view_aura.cc

Index: content/browser/renderer_host/render_widget_host_view_aura.cc
diff --git a/content/browser/renderer_host/render_widget_host_view_aura.cc b/content/browser/renderer_host/render_widget_host_view_aura.cc
index eee2df69b76756f82a597511cb8b934f22227e9e..b503b90476ed30c5193c6d2f48fe258e90289f60 100644
--- a/content/browser/renderer_host/render_widget_host_view_aura.cc
+++ b/content/browser/renderer_host/render_widget_host_view_aura.cc
@@ -17,7 +17,6 @@
 #include "cc/output/copy_output_request.h"
 #include "cc/output/copy_output_result.h"
 #include "cc/resources/texture_mailbox.h"
-#include "cc/trees/layer_tree_settings.h"
 #include "content/browser/accessibility/browser_accessibility_manager.h"
 #include "content/browser/accessibility/browser_accessibility_state_impl.h"
 #include "content/browser/frame_host/frame_tree.h"
@@ -61,7 +60,6 @@
 #include "ui/base/hit_test.h"
 #include "ui/base/ime/input_method.h"
 #include "ui/base/ui_base_types.h"
-#include "ui/compositor/compositor_vsync_manager.h"
 #include "ui/compositor/dip_util.h"
 #include "ui/events/event.h"
 #include "ui/events/event_utils.h"
@@ -452,6 +450,8 @@ RenderWidgetHostViewAura::RenderWidgetHostViewAura(RenderWidgetHost* host)
 #endif
       has_snapped_to_boundary_(false),
       touch_editing_client_(NULL),
+      needs_begin_frame_(false),
+      begin_frame_scheduling_is_enabled_(false),
       weak_ptr_factory_(this) {
   host_->SetView(this);
   window_observer_.reset(new WindowObserver(this));
@@ -465,11 +465,24 @@ RenderWidgetHostViewAura::RenderWidgetHostViewAura(RenderWidgetHost* host)
   bool overscroll_enabled = CommandLine::ForCurrentProcess()->
       GetSwitchValueASCII(switches::kOverscrollHistoryNavigation) != "0";
   SetOverscrollControllerEnabled(overscroll_enabled);
+
+#if !defined(OS_CHROMEOS)
+  begin_frame_scheduling_is_enabled_ = true;

[brianderson, 2014/09/04 18:45:46]

Can we assume this is true for all Aura platforms?

+#endif
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // RenderWidgetHostViewAura, RenderWidgetHostView implementation:
 
+bool RenderWidgetHostViewAura::OnMessageReceived(const IPC::Message& msg) {
+  bool handled = true;
+  IPC_BEGIN_MESSAGE_MAP(RenderWidgetHostViewAura, msg)
+    IPC_MESSAGE_HANDLER(ViewHostMsg_SetNeedsBeginFrame, OnSetNeedsBeginFrame)
+    IPC_MESSAGE_UNHANDLED(handled = false)
+  IPC_END_MESSAGE_MAP()
+  return handled;
+}
+
 void RenderWidgetHostViewAura::InitAsChild(
     gfx::NativeView parent_view) {
   window_->SetType(ui::wm::WINDOW_TYPE_CONTROL);
@@ -860,6 +873,14 @@ void RenderWidgetHostViewAura::Destroy() {
   // Beware, this function is not called on all destruction paths. It will
   // implicitly end up calling ~RenderWidgetHostViewAura though, so all
   // destruction/cleanup code should happen there, not here.

[piman, 2014/09/04 20:56:38]

Beware of this comment!

+
+  // Remove observation from Compositor in here because we can't access
+  // to compositor in destructor.
+  if (needs_begin_frame_ && GetCompositor()) {
+    GetCompositor()->RemoveBeginFrameObserver(this);
+    needs_begin_frame_ = false;
+  }
+
   in_shutdown_ = true;
   delete window_;
 }
@@ -2119,9 +2140,30 @@ void RenderWidgetHostViewAura::OnHostMoved(const aura::WindowTreeHost* host,
 }
 
 ////////////////////////////////////////////////////////////////////////////////
+// ui::CompositorBeginFrameObserver implementation:
+void RenderWidgetHostViewAura::OnSendBeginFrame(
+    const cc::BeginFrameArgs& args) {
+  DCHECK(begin_frame_scheduling_is_enabled_);
+  DCHECK(host_);
+  TRACE_EVENT0("cc", "RenderWidgetHostViewAura::OnSendBeginFrame");
+
+  delegated_frame_host_->UpdateVSyncParameters(args);
+
+  host_->Send(new ViewMsg_BeginFrame(host_->GetRoutingID(), args));
+
+  last_begin_frame_args_ = args;
+}
+
+////////////////////////////////////////////////////////////////////////////////
 // RenderWidgetHostViewAura, private:
 
 RenderWidgetHostViewAura::~RenderWidgetHostViewAura() {
+  // When we are using unified BeginFrame(--enable-begin-frame-scheduling),
+  // |needs_begin_frame_| always be false in here. We can't remove
+  // observation from Compositor in this function because |window_| is already
+  // removed from window tree host.
+  DCHECK(!needs_begin_frame_);
+
   if (touch_editing_client_)
     touch_editing_client_->OnViewDestroyed();
 
@@ -2379,6 +2421,13 @@ void RenderWidgetHostViewAura::AddedToRootWindow() {
 #endif
 
   delegated_frame_host_->AddedToWindow();
+
+  // When this RWHV is added to new root window, this RWHV should be added to
+  // the new compositor.
+  if (needs_begin_frame_) {
+    DCHECK(begin_frame_scheduling_is_enabled_);
+    GetCompositor()->AddBeginFrameObserver(this, last_begin_frame_args_);
+  }

[piman, 2014/09/04 20:56:38]

A lot of this logic is common between mac and aura. Can it be moved into
DelegatedFrameHost?

 }
 
 void RenderWidgetHostViewAura::RemovingFromRootWindow() {
@@ -2398,6 +2447,13 @@ void RenderWidgetHostViewAura::RemovingFromRootWindow() {
   if (legacy_render_widget_host_HWND_)
     legacy_render_widget_host_HWND_->UpdateParent(::GetDesktopWindow());
 #endif
+
+  // When this RWHV is removed from current root window, this RWHV should be
+  // removed from the current compositor which will be removed.
+  if (needs_begin_frame_) {
+    DCHECK(begin_frame_scheduling_is_enabled_);
+    GetCompositor()->RemoveBeginFrameObserver(this);
+  }
 }
 
 void RenderWidgetHostViewAura::DetachFromInputMethod() {
@@ -2439,6 +2495,23 @@ SkColorType RenderWidgetHostViewAura::PreferredReadbackFormat() {
   return kN32_SkColorType;
 }
 
+void RenderWidgetHostViewAura::OnSetNeedsBeginFrame(bool enabled) {
+  DCHECK(begin_frame_scheduling_is_enabled_);
+  DCHECK(GetCompositor());
+
+  if (needs_begin_frame_ == enabled)
+    return;
+
+  TRACE_EVENT1("cc", "RenderWidgetHostViewAura::OnSetNeedsBeginFrame",
+               "enabled", enabled);
+  if (enabled)
+    GetCompositor()->AddBeginFrameObserver(this, last_begin_frame_args_);
+  else
+    GetCompositor()->RemoveBeginFrameObserver(this);
+
+  needs_begin_frame_ = enabled;
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 // DelegatedFrameHost, public: