Make WebWidget::resize early out if the size doesn't change.

content/renderer/render_widget.cc

 // Copyright (c) 2012 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/renderer/render_widget.h"
 
 #include <memory>
 #include <utility>
 
 #include "base/auto_reset.h"
@@ skipping 659 matching lines @@
     std::unique_ptr<cc::SwapPromiseMonitor> latency_info_swap_promise_monitor(
         compositor_->CreateLatencyInfoSwapPromiseMonitor(&swap_latency_info));
     compositor_->SetNeedsForcedRedraw();
   }
   ScheduleComposite();
 }
 
 void RenderWidget::OnRequestMoveAck() {
   DCHECK(pending_window_rect_count_);
   pending_window_rect_count_--;
+  if (!pending_window_rect_count_)
+    view_screen_rect_ = pending_window_rect_;
 }
 
 GURL RenderWidget::GetURLForGraphicsContext3D() {
   return GURL();
 }
 
 void RenderWidget::OnHandleInputEvent(const blink::WebInputEvent* input_event,
                                       const ui::LatencyInfo& latency_info,
                                       InputEventDispatchType dispatch_type) {
   if (!input_event)
@@ skipping 437 matching lines @@
     DCHECK(!params.needs_resize_ack || !next_paint_is_resize_ack());
   }
 
   // Ignore this during shutdown.
   if (!webwidget_)
     return;
 
   if (compositor_)
     compositor_->setViewportSize(params.physical_backing_size);
 
-  bool resized = size_ != params.new_size ||
-                 physical_backing_size_ != params.physical_backing_size;
-
   size_ = params.new_size;
   physical_backing_size_ = params.physical_backing_size;
 
   top_controls_shrink_blink_size_ = params.top_controls_shrink_blink_size;
   top_controls_height_ = params.top_controls_height;
   visible_viewport_size_ = params.visible_viewport_size;
   resizer_rect_ = params.resizer_rect;
 
   // NOTE: We may have entered fullscreen mode without changing our size.
   bool fullscreen_change =
       is_fullscreen_granted_ != params.is_fullscreen_granted;
   is_fullscreen_granted_ = params.is_fullscreen_granted;
   display_mode_ = params.display_mode;
 
   webwidget_->setTopControlsHeight(params.top_controls_height,
                                    top_controls_shrink_blink_size_);
 
-  if (resized) {
-    gfx::Size new_widget_size = size_;
-    if (IsUseZoomForDSFEnabled()) {
-      new_widget_size = gfx::ScaleToCeiledSize(new_widget_size,
-                                               GetOriginalDeviceScaleFactor());
-    }
-    // When resizing, we want to wait to paint before ACK'ing the resize.  This
-    // ensures that we only resize as fast as we can paint.  We only need to
-    // send an ACK if we are resized to a non-empty rect.
-    webwidget_->resize(new_widget_size);
+  gfx::Size new_widget_size = size_;
+  if (IsUseZoomForDSFEnabled()) {
+    new_widget_size = gfx::ScaleToCeiledSize(new_widget_size,
+                                             GetOriginalDeviceScaleFactor());
   }
+  // When resizing, we want to wait to paint before ACK'ing the resize.  This
+  // ensures that we only resize as fast as we can paint.  We only need to
+  // send an ACK if we are resized to a non-empty rect.
+  webwidget_->resize(new_widget_size);
+
   WebSize visual_viewport_size;
 
   if (IsUseZoomForDSFEnabled()) {
     visual_viewport_size = gfx::ScaleToCeiledSize(
         params.visible_viewport_size,
         GetOriginalDeviceScaleFactor());
   } else {
     visual_viewport_size = visible_viewport_size_;
   }
 
@@ skipping 933 matching lines @@
 }
 
 float RenderWidget::GetOriginalDeviceScaleFactor() const {
   return
       screen_metrics_emulator_ ?
       screen_metrics_emulator_->original_screen_info().deviceScaleFactor :
       device_scale_factor_;
 }
 
 }  // namespace content