Revert of cc: Make scheduling be driven by vsync for android webview.

android_webview/browser/browser_view_renderer.cc

 // Copyright 2014 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 "android_webview/browser/browser_view_renderer.h"
 
 #include "android_webview/browser/browser_view_renderer_client.h"
 #include "android_webview/browser/child_frame.h"
 #include "base/auto_reset.h"
 #include "base/command_line.h"
@@ skipping 80 matching lines @@
       is_paused_(false),
       view_visible_(false),
       window_visible_(false),
       attached_to_window_(false),
       hardware_enabled_(false),
       dip_scale_(0.0),
       page_scale_factor_(1.0),
       on_new_picture_enable_(false),
       clear_view_(false),
       offscreen_pre_raster_(false),
+      compositor_needs_continuous_invalidate_(false),
+      block_invalidates_(false),
       fallback_tick_pending_(false) {
 }
 
 BrowserViewRenderer::~BrowserViewRenderer() {
 }
 
 void BrowserViewRenderer::RegisterWithWebContents(
     content::WebContents* web_contents) {
   web_contents->SetUserData(kBrowserViewRendererUserDataKey,
                             new BrowserViewRendererUserData(this));
@@ skipping 78 matching lines @@
     TRACE_EVENT_INSTANT0("android_webview", "EarlyOut_ClearView",
                          TRACE_EVENT_SCOPE_THREAD);
     return false;
   }
 
   return true;
 }
 
 bool BrowserViewRenderer::OnDrawHardware() {
   TRACE_EVENT0("android_webview", "BrowserViewRenderer::OnDrawHardware");
-
   shared_renderer_state_.InitializeHardwareDrawIfNeededOnUI();
 
   if (!CanOnDraw()) {
     return false;
   }
 
   shared_renderer_state_.SetScrollOffsetOnUI(last_on_draw_scroll_offset_);
 
   if (!hardware_enabled_) {
     TRACE_EVENT0("android_webview", "InitializeHwDraw");
     hardware_enabled_ = compositor_->InitializeHwDraw();
   }
   if (!hardware_enabled_) {
     TRACE_EVENT_INSTANT0("android_webview", "EarlyOut_HardwareNotEnabled",
                          TRACE_EVENT_SCOPE_THREAD);
     return false;
   }
 
   return CompositeHw();
 }
 
 bool BrowserViewRenderer::CompositeHw() {
-  CancelFallbackTick();
-
   ReturnResourceFromParent();
   compositor_->SetMemoryPolicy(CalculateDesiredMemoryPolicy());
 
   ParentCompositorDrawConstraints parent_draw_constraints =
       shared_renderer_state_.GetParentDrawConstraintsOnUI();
   gfx::Size surface_size(size_);
   gfx::Rect viewport(surface_size);
   gfx::Rect clip = viewport;
   gfx::Transform transform_for_tile_priority =
       parent_draw_constraints.transform;
@@ skipping 23 matching lines @@
     TRACE_EVENT_INSTANT0("android_webview", "NoNewFrame",
                          TRACE_EVENT_SCOPE_THREAD);
     return false;
   }
 
   scoped_ptr<ChildFrame> child_frame = make_scoped_ptr(
       new ChildFrame(frame.Pass(), viewport_rect_for_tile_priority,
                      transform_for_tile_priority, offscreen_pre_raster_,
                      parent_draw_constraints.is_layer));
 
+  DidComposite();
   // Uncommitted frame can happen with consecutive fallback ticks.
   ReturnUnusedResource(shared_renderer_state_.PassUncommittedFrameOnUI());
   shared_renderer_state_.SetCompositorFrameOnUI(child_frame.Pass());
   return true;
 }
 
 void BrowserViewRenderer::UpdateParentDrawConstraints() {
-  PostInvalidateWithFallback();
+  EnsureContinuousInvalidation(true);
   ParentCompositorDrawConstraints parent_draw_constraints =
       shared_renderer_state_.GetParentDrawConstraintsOnUI();
   client_->ParentDrawConstraintsUpdated(parent_draw_constraints);
 }
 
 void BrowserViewRenderer::ReturnUnusedResource(
     scoped_ptr<ChildFrame> child_frame) {
   if (!child_frame.get() || !child_frame->frame.get())
     return;
 
@@ skipping 50 matching lines @@
 
 void BrowserViewRenderer::ClearView() {
   TRACE_EVENT_INSTANT0("android_webview",
                        "BrowserViewRenderer::ClearView",
                        TRACE_EVENT_SCOPE_THREAD);
   if (clear_view_)
     return;
 
   clear_view_ = true;
   // Always invalidate ignoring the compositor to actually clear the webview.
-  PostInvalidateWithFallback();
+  EnsureContinuousInvalidation(true);
 }
 
 void BrowserViewRenderer::SetOffscreenPreRaster(bool enable) {
   // TODO(hush): anything to do when the setting is toggled?
   offscreen_pre_raster_ = enable;
 }
 
 void BrowserViewRenderer::SetIsPaused(bool paused) {
   TRACE_EVENT_INSTANT1("android_webview",
                        "BrowserViewRenderer::SetIsPaused",
                        TRACE_EVENT_SCOPE_THREAD,
                        "paused",
                        paused);
   is_paused_ = paused;
-  UpdateCompositorIsActive();
+  EnsureContinuousInvalidation(false);
 }
 
 void BrowserViewRenderer::SetViewVisibility(bool view_visible) {
   TRACE_EVENT_INSTANT1("android_webview",
                        "BrowserViewRenderer::SetViewVisibility",
                        TRACE_EVENT_SCOPE_THREAD,
                        "view_visible",
                        view_visible);
   view_visible_ = view_visible;
 }
 
 void BrowserViewRenderer::SetWindowVisibility(bool window_visible) {
   TRACE_EVENT_INSTANT1("android_webview",
                        "BrowserViewRenderer::SetWindowVisibility",
                        TRACE_EVENT_SCOPE_THREAD,
                        "window_visible",
                        window_visible);
   window_visible_ = window_visible;
-  UpdateCompositorIsActive();
+  EnsureContinuousInvalidation(false);
 }
 
 void BrowserViewRenderer::OnSizeChanged(int width, int height) {
   TRACE_EVENT_INSTANT2("android_webview",
                        "BrowserViewRenderer::OnSizeChanged",
                        TRACE_EVENT_SCOPE_THREAD,
                        "width",
                        width,
                        "height",
                        height);
   size_.SetSize(width, height);
 }
 
 void BrowserViewRenderer::OnAttachedToWindow(int width, int height) {
   TRACE_EVENT2("android_webview",
                "BrowserViewRenderer::OnAttachedToWindow",
                "width",
                width,
                "height",
                height);
   attached_to_window_ = true;
   size_.SetSize(width, height);
-  UpdateCompositorIsActive();
 }
 
 void BrowserViewRenderer::OnDetachedFromWindow() {
   TRACE_EVENT0("android_webview", "BrowserViewRenderer::OnDetachedFromWindow");
   shared_renderer_state_.ReleaseHardwareDrawIfNeededOnUI();
   attached_to_window_ = false;
   DCHECK(!hardware_enabled_);
-  UpdateCompositorIsActive();
 }
 
 void BrowserViewRenderer::ReleaseHardware() {
   DCHECK(hardware_enabled_);
   ReturnUnusedResource(shared_renderer_state_.PassUncommittedFrameOnUI());
   ReturnResourceFromParent();
   DCHECK(shared_renderer_state_.ReturnedResourcesEmptyOnUI());
 
   if (compositor_) {
     compositor_->ReleaseHwDraw();
@@ skipping 11 matching lines @@
   return gfx::Rect(client_->GetLocationOnScreen(), size_);
 }
 
 void BrowserViewRenderer::DidInitializeCompositor(
     content::SynchronousCompositor* compositor) {
   TRACE_EVENT0("android_webview",
                "BrowserViewRenderer::DidInitializeCompositor");
   DCHECK(compositor);
   DCHECK(!compositor_);
   compositor_ = compositor;
-  UpdateCompositorIsActive();
 }
 
 void BrowserViewRenderer::DidDestroyCompositor(
     content::SynchronousCompositor* compositor) {
   TRACE_EVENT0("android_webview", "BrowserViewRenderer::DidDestroyCompositor");
   DCHECK(compositor_);
   compositor_ = NULL;
 }
 
+void BrowserViewRenderer::SetContinuousInvalidate(bool invalidate) {
+  if (compositor_needs_continuous_invalidate_ == invalidate)
+    return;
+
+  TRACE_EVENT_INSTANT1("android_webview",
+                       "BrowserViewRenderer::SetContinuousInvalidate",
+                       TRACE_EVENT_SCOPE_THREAD,
+                       "invalidate",
+                       invalidate);
+  compositor_needs_continuous_invalidate_ = invalidate;
+
+  EnsureContinuousInvalidation(false);
+}
+
 void BrowserViewRenderer::SetDipScale(float dip_scale) {
   dip_scale_ = dip_scale;
   CHECK_GT(dip_scale_, 0.f);
 }
 
 gfx::Vector2d BrowserViewRenderer::max_scroll_offset() const {
   DCHECK_GT(dip_scale_, 0.f);
   return gfx::ToCeiledVector2d(gfx::ScaleVector2d(
       max_scroll_offset_dip_, dip_scale_ * page_scale_factor_));
 }
@@ skipping 147 matching lines @@
     overscroll_rounding_error_ = gfx::Vector2dF();
   gfx::Vector2dF scaled_overscroll_delta =
       gfx::ScaleVector2d(latest_overscroll_delta, physical_pixel_scale);
   gfx::Vector2d rounded_overscroll_delta = gfx::ToRoundedVector2d(
       scaled_overscroll_delta + overscroll_rounding_error_);
   overscroll_rounding_error_ =
       scaled_overscroll_delta - rounded_overscroll_delta;
   client_->DidOverscroll(rounded_overscroll_delta);
 }
 
-void BrowserViewRenderer::PostInvalidate() {
-  TRACE_EVENT_INSTANT0("android_webview", "BrowserViewRenderer::PostInvalidate",
-                       TRACE_EVENT_SCOPE_THREAD);
-  PostInvalidateWithFallback();
-}
+void BrowserViewRenderer::EnsureContinuousInvalidation(bool force_invalidate) {
+  // This method should be called again when any of these conditions change.
+  bool need_invalidate =
+      compositor_needs_continuous_invalidate_ || force_invalidate;
+  if (!need_invalidate || block_invalidates_)
+    return;
 
-void BrowserViewRenderer::PostInvalidateWithFallback() {
   // Always call view invalidate. We rely the Android framework to ignore the
   // invalidate when it's not needed such as when view is not visible.
   client_->PostInvalidate();
 
   // Stop fallback ticks when one of these is true.
   // 1) Webview is paused. Also need to check we are not in clear view since
   // paused, offscreen still expect clear view to recover.
   // 2) If we are attached to window and the window is not visible (eg when
   // app is in the background). We are sure in this case the webview is used
   // "on-screen" but that updates are not needed when in the background.
   bool throttle_fallback_tick =
       (is_paused_ && !clear_view_) || (attached_to_window_ && !window_visible_);
-
-  if (throttle_fallback_tick || fallback_tick_pending_)
+  if (throttle_fallback_tick)
     return;
 
-  DCHECK(post_fallback_tick_.IsCancelled());
-  DCHECK(fallback_tick_fired_.IsCancelled());
+  block_invalidates_ = compositor_needs_continuous_invalidate_;
+  if (fallback_tick_pending_)
+    return;
 
+  // Unretained here is safe because the callbacks are cancelled when
+  // they are destroyed.
   post_fallback_tick_.Reset(base::Bind(&BrowserViewRenderer::PostFallbackTick,
                                        base::Unretained(this)));
-  ui_task_runner_->PostTask(FROM_HERE, post_fallback_tick_.callback());
-  fallback_tick_pending_ = true;
-}
-
-void BrowserViewRenderer::CancelFallbackTick() {
-  post_fallback_tick_.Cancel();
   fallback_tick_fired_.Cancel();
   fallback_tick_pending_ = false;
+
+  // No need to reschedule fallback tick if compositor does not need to be
+  // ticked. This can happen if this is reached because force_invalidate is
+  // true.
+  if (compositor_needs_continuous_invalidate_) {
+    fallback_tick_pending_ = true;
+    ui_task_runner_->PostTask(FROM_HERE, post_fallback_tick_.callback());
+  }
 }
 
 void BrowserViewRenderer::PostFallbackTick() {
   DCHECK(fallback_tick_fired_.IsCancelled());
-  TRACE_EVENT0("android_webview", "BrowserViewRenderer::PostFallbackTick");
-  post_fallback_tick_.Cancel();
   fallback_tick_fired_.Reset(base::Bind(&BrowserViewRenderer::FallbackTickFired,
                                         base::Unretained(this)));
-  ui_task_runner_->PostDelayedTask(
-      FROM_HERE, fallback_tick_fired_.callback(),
-      base::TimeDelta::FromMilliseconds(kFallbackTickTimeoutInMilliseconds));
+  if (compositor_needs_continuous_invalidate_) {
+    ui_task_runner_->PostDelayedTask(
+        FROM_HERE,
+        fallback_tick_fired_.callback(),
+        base::TimeDelta::FromMilliseconds(kFallbackTickTimeoutInMilliseconds));
+  } else {
+    // Pretend we just composited to unblock further invalidates.
+    DidComposite();
+  }
 }
 
 void BrowserViewRenderer::FallbackTickFired() {
-  TRACE_EVENT0("android_webview", "BrowserViewRenderer::FallbackTickFired");
+  TRACE_EVENT1("android_webview",
+               "BrowserViewRenderer::FallbackTickFired",
+               "compositor_needs_continuous_invalidate_",
+               compositor_needs_continuous_invalidate_);
+
   // This should only be called if OnDraw or DrawGL did not come in time, which
-  // means fallback_tick_pending_ must still be true.
-  DCHECK(fallback_tick_pending_);
-  fallback_tick_fired_.Cancel();
+  // means block_invalidates_ must still be true.
+  DCHECK(block_invalidates_);
   fallback_tick_pending_ = false;
-  if (compositor_) {
+  if (compositor_needs_continuous_invalidate_ && compositor_) {
     if (hardware_enabled_) {
       CompositeHw();
     } else {
       ForceFakeCompositeSW();
     }
+  } else {
+    // Pretend we just composited to unblock further invalidates.
+    DidComposite();
   }
 }
 
 void BrowserViewRenderer::ForceFakeCompositeSW() {
   DCHECK(compositor_);
   SkBitmap bitmap;
   bitmap.allocN32Pixels(1, 1);
   bitmap.eraseColor(0);
   SkCanvas canvas(bitmap);
   CompositeSW(&canvas);
 }
 
 bool BrowserViewRenderer::CompositeSW(SkCanvas* canvas) {
   DCHECK(compositor_);
-  CancelFallbackTick();
   ReturnResourceFromParent();
-  return compositor_->DemandDrawSw(canvas);
+  bool result = compositor_->DemandDrawSw(canvas);
+  DidComposite();
+  return result;
 }
 
-void BrowserViewRenderer::UpdateCompositorIsActive() {
-  if (compositor_)
-    compositor_->SetIsActive(!is_paused_ &&
-                             (!attached_to_window_ || window_visible_));
+void BrowserViewRenderer::DidComposite() {
+  block_invalidates_ = false;
+  post_fallback_tick_.Cancel();
+  fallback_tick_fired_.Cancel();
+  fallback_tick_pending_ = false;
+  EnsureContinuousInvalidation(false);
 }
 
 std::string BrowserViewRenderer::ToString() const {
   std::string str;
   base::StringAppendF(&str, "is_paused: %d ", is_paused_);
   base::StringAppendF(&str, "view_visible: %d ", view_visible_);
   base::StringAppendF(&str, "window_visible: %d ", window_visible_);
   base::StringAppendF(&str, "dip_scale: %f ", dip_scale_);
   base::StringAppendF(&str, "page_scale_factor: %f ", page_scale_factor_);
-  base::StringAppendF(&str, "fallback_tick_pending: %d ",
-                      fallback_tick_pending_);
+  base::StringAppendF(&str,
+                      "compositor_needs_continuous_invalidate: %d ",
+                      compositor_needs_continuous_invalidate_);
+  base::StringAppendF(&str, "block_invalidates: %d ", block_invalidates_);
   base::StringAppendF(&str, "view size: %s ", size_.ToString().c_str());
   base::StringAppendF(&str, "attached_to_window: %d ", attached_to_window_);
   base::StringAppendF(&str,
                       "global visible rect: %s ",
                       last_on_draw_global_visible_rect_.ToString().c_str());
   base::StringAppendF(
       &str, "scroll_offset_dip: %s ", scroll_offset_dip_.ToString().c_str());
   base::StringAppendF(&str,
                       "overscroll_rounding_error_: %s ",
                       overscroll_rounding_error_.ToString().c_str());
   base::StringAppendF(
       &str, "on_new_picture_enable: %d ", on_new_picture_enable_);
   base::StringAppendF(&str, "clear_view: %d ", clear_view_);
   return str;
 }
 
 }  // namespace android_webview