Make window resize using CoreAnimation behave the same as without.

Change the NSView to update the layer when setNeedsDisplay is called and
add a call to the layer's setNeedsDisplay in the NSView's setFrameSize.

This has the consequnece that drawLayer will be called inside the call
to setNeedsDisplay.

Make the call to drawLayer (for the composited path) block until a frame
of the new window size is received.

Add all of this together, and the setFrameSize call will block until a
frame of the right size is received. This may not be the best thing, as
it blocks the browser's main thread (which will jank any animations in
other windows), but it matches the non-CoreAnimation behavior.

Of note is that setting the NSView to have the redraw policy of
NSViewLayerContentsRedrawDuringViewResize and not adding the
setNeedsDisplay call in setFrameSize does not result in the setFrameSize
call blocking in time, and so the window contents lag during resize.

BUG=254629

Review URL: https://chromiumcodereview.appspot.com/18029025

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@209678 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 25 insertions, 0 deletions

diff --git a/content/browser/renderer_host/compositing_iosurface_layer_mac.mm b/content/browser/renderer_host/compositing_iosurface_layer_mac.mm
index 10b0727..47878a0 100644
--- a/content/browser/renderer_host/compositing_iosurface_layer_mac.mm
+++ b/content/browser/renderer_host/compositing_iosurface_layer_mac.mm
@@ -8,6 +8,7 @@
 #include <OpenGL/gl.h>
 
 #include "base/mac/sdk_forward_declarations.h"
+#include "content/browser/renderer_host/render_widget_host_impl.h"
 #include "content/browser/renderer_host/render_widget_host_view_mac.h"
 #include "content/browser/renderer_host/compositing_iosurface_context_mac.h"
 #include "content/browser/renderer_host/compositing_iosurface_mac.h"
@@ -100,6 +101,8 @@
              pixelFormat:(CGLPixelFormatObj)pixelFormat
             forLayerTime:(CFTimeInterval)timeInterval
              displayTime:(const CVTimeStamp*)timeStamp {
+  TRACE_EVENT0("browser", "CompositingIOSurfaceLayer::drawInCGLContext");
+
   if (!context_.get() || !renderWidgetHostView_ ||
       !renderWidgetHostView_->compositing_iosurface_) {
     glClearColor(1, 1, 1, 1);
@@ -109,6 +112,17 @@
 
   DCHECK(glContext == context_->cgl_context());
 
+  // If a resize is in progress then GetBackingStore request a frame of the
+  // current window size and block until a frame of the right size comes in.
+  // This makes the window content not lag behind the resize (at the cost of
+  // blocking on the browser's main thread).
+  if (renderWidgetHostView_->render_widget_host_) {
+    renderWidgetHostView_->about_to_validate_and_paint_ = true;
+    (void)renderWidgetHostView_->render_widget_host_->GetBackingStore(true);
+    renderWidgetHostView_->about_to_validate_and_paint_ = false;
+    CGLSetCurrentContext(glContext);
+  }
+
   gfx::Size window_size([self frame].size);
   float window_scale_factor = 1.f;
   if ([self respondsToSelector:(@selector(contentsScale))])
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 4349775..47d617c 100644
--- a/content/browser/renderer_host/render_widget_host_view_mac.mm
+++ b/content/browser/renderer_host/render_widget_host_view_mac.mm
@@ -2465,6 +2465,8 @@ void RenderWidgetHostViewMac::FrameSwapped() {
 }
 
 - (void)setFrameSize:(NSSize)newSize {
+  TRACE_EVENT0("browser", "RenderWidgetHostViewCocoa::setFrameSize");
+
   // NB: -[NSView setFrame:] calls through -setFrameSize:, so overriding
   // -setFrame: isn't neccessary.
   [super setFrameSize:newSize];
@@ -2472,6 +2474,13 @@ void RenderWidgetHostViewMac::FrameSwapped() {
     renderWidgetHostView_->render_widget_host_->SendScreenRects();
     renderWidgetHostView_->render_widget_host_->WasResized();
   }
+
+  // This call is necessary to make the window wait for a new frame at the new
+  // size to be available before the resize completes. Calling only
+  // setLayerContentsRedrawPolicy:NSViewLayerContentsRedrawOnSetNeedsDisplay on
+  // this is not sufficient.
+  [renderWidgetHostView_->software_layer_ setNeedsDisplay];
+  [renderWidgetHostView_->compositing_iosurface_layer_ setNeedsDisplay];
 }
 
 - (void)callSetNeedsDisplayInRect {
@@ -3649,6 +3658,8 @@ extern NSString *NSTextInputReplacementRangeAttributeName;
 // Delegate methods for the software CALayer
 - (void)drawLayer:(CALayer*)layer
         inContext:(CGContextRef)context {
+  TRACE_EVENT0("browser", "CompositingIOSurfaceLayer::drawLayer");
+
   DCHECK(renderWidgetHostView_->use_core_animation_);
   DCHECK([layer isEqual:renderWidgetHostView_->software_layer_]);