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content/browser/renderer_host/render_widget_host_view_mac.mm

Index: content/browser/renderer_host/render_widget_host_view_mac.mm
diff --git a/content/browser/renderer_host/render_widget_host_view_mac.mm b/content/browser/renderer_host/render_widget_host_view_mac.mm
index b26950a38ba9f40d7a2dd2e636831f040d3117e0..1ed5f36bb53763af3df07ef5cdf0089ee5a0d614 100644
--- a/content/browser/renderer_host/render_widget_host_view_mac.mm
+++ b/content/browser/renderer_host/render_widget_host_view_mac.mm
@@ -70,6 +70,7 @@
 #include "ui/compositor/compositor.h"
 #include "ui/compositor/layer.h"
 #include "ui/gfx/display.h"
+#include "ui/gfx/frame_time.h"
 #include "ui/gfx/point.h"
 #include "ui/gfx/rect_conversions.h"
 #include "ui/gfx/scoped_ns_graphics_context_save_gstate_mac.h"
@@ -851,12 +852,13 @@ void RenderWidgetHostViewMac::SendVSyncParametersToRenderer() {
   if (!render_widget_host_ || !display_link_)
     return;
 
-  base::TimeTicks timebase;
-  base::TimeDelta interval;
-  if (!display_link_->GetVSyncParameters(&timebase, &interval))
+  if (!display_link_->GetVSyncParameters(&vsync_timebase_, &vsync_interval_)) {
+    vsync_timebase_ = base::TimeTicks();
+    vsync_interval_ = base::TimeDelta();
     return;
+  }
 
-  render_widget_host_->UpdateVSyncParameters(timebase, interval);
+  render_widget_host_->UpdateVSyncParameters(vsync_timebase_, vsync_interval_);
 }
 
 void RenderWidgetHostViewMac::UpdateBackingStoreScaleFactor() {
@@ -1415,6 +1417,7 @@ void RenderWidgetHostViewMac::PluginImeCompositionCompleted(
 
 void RenderWidgetHostViewMac::CompositorSwapBuffers(
     IOSurfaceID surface_handle,
+    const gfx::Rect& damage_rect,
     const gfx::Size& size,
     float surface_scale_factor,
     const std::vector<ui::LatencyInfo>& latency_info) {
@@ -1473,11 +1476,20 @@ void RenderWidgetHostViewMac::CompositorSwapBuffers(
   // current context afterward.
   bool frame_was_captured = false;
   if (frame_subscriber_) {
-    const base::TimeTicks present_time = base::TimeTicks::Now();
+    const base::TimeTicks now = gfx::FrameTime::Now();
+    base::TimeTicks present_time;
+    if (vsync_timebase_.is_null() || vsync_interval_ <= base::TimeDelta()) {
+      present_time = now;
+    } else {
+      const int64 intervals_elapsed = (now - vsync_timebase_) / vsync_interval_;
+      present_time = vsync_timebase_ +
+          (intervals_elapsed + 1) * vsync_interval_;
+    }
+
     scoped_refptr<media::VideoFrame> frame;
     RenderWidgetHostViewFrameSubscriber::DeliverFrameCallback callback;
-    if (frame_subscriber_->ShouldCaptureFrame(present_time,
-                                              &frame, &callback)) {
+    if (frame_subscriber_->ShouldCaptureFrame(
+            damage_rect, present_time, &frame, &callback)) {
       // Flush the context that updated the IOSurface, to ensure that the
       // context that does the copy picks up the correct version.
       {
@@ -1733,6 +1745,7 @@ void RenderWidgetHostViewMac::AcceleratedSurfaceBuffersSwapped(
           params.surface_handle);
 
       CompositorSwapBuffers(io_surface_id,
+                            gfx::Rect(),
                             params.size,
                             params.scale_factor,
                             params.latency_info);
@@ -1777,10 +1790,12 @@ void RenderWidgetHostViewMac::AcceleratedSurfacePostSubBuffer(
                     gpu_host_id,
                     compositing_iosurface_ ?
                         compositing_iosurface_->GetRendererID() : 0);
-  CompositorSwapBuffers(IOSurfaceIDFromSurfaceHandle(params.surface_handle),
-                        params.surface_size,
-                        params.surface_scale_factor,
-                        params.latency_info);
+  CompositorSwapBuffers(
+      IOSurfaceIDFromSurfaceHandle(params.surface_handle),
+      gfx::Rect(params.x, params.y, params.width, params.height),
+      params.surface_size,
+      params.surface_scale_factor,
+      params.latency_info);
 }
 
 void RenderWidgetHostViewMac::AcceleratedSurfaceSuspend() {