Update IOSurface scale factor before compare

content/browser/renderer_host/compositing_iosurface_mac.mm

 // 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/browser/renderer_host/compositing_iosurface_mac.h"
 
 #include <OpenGL/CGLRenderers.h>
 #include <OpenGL/OpenGL.h>
 
 #include "base/bind.h"
@@ skipping 306 matching lines @@
   // Having two NSOpenGLContexts bound to an NSView concurrently will cause
   // artifacts and crashes. If |context_| is bound to |view|, then unbind
   // |context_| before |new_context| gets bound to |view|.
   // http://crbug.com/230883
   if ([context_->nsgl_context() view] == view)
     [context_->nsgl_context() clearDrawable];
 
   context_ = new_context;
 }
 
+void CompositingIOSurfaceMac::SetDeviceScaleFactor(float scale_factor) {
+  // TODO: After a resolution change, the DPI-ness of the view and the
+  // IOSurface might not be in sync.
+  io_surface_size_ = gfx::ToFlooredSize(
+      gfx::ScaleSize(pixel_io_surface_size_, 1.0 / scale_factor));
+}
+
 bool CompositingIOSurfaceMac::is_vsync_disabled() const {
   return context_->is_vsync_disabled();
 }
 
 void CompositingIOSurfaceMac::GetVSyncParameters(base::TimeTicks* timebase,
                                                  uint32* interval_numerator,
                                                  uint32* interval_denominator) {
   base::AutoLock lock(lock_);
   *timebase = vsync_timebase_;
   *interval_numerator = vsync_interval_numerator_;
@@ skipping 40 matching lines @@
 
   TRACE_EVENT1("browser", "CompositingIOSurfaceMac::DrawIOSurface",
                "has_io_surface", has_io_surface);
 
   [context_->nsgl_context() setView:view];
   gfx::Size window_size(NSSizeToCGSize([view frame].size));
   gfx::Size pixel_window_size = gfx::ToFlooredSize(
       gfx::ScaleSize(window_size, scale_factor));
   glViewport(0, 0, pixel_window_size.width(), pixel_window_size.height());
 
-  // TODO: After a resolution change, the DPI-ness of the view and the
-  // IOSurface might not be in sync.
-  io_surface_size_ = gfx::ToFlooredSize(
-      gfx::ScaleSize(pixel_io_surface_size_, 1.0 / scale_factor));
-  quad_.set_size(io_surface_size_, pixel_io_surface_size_);
+  SetDeviceScaleFactor(scale_factor);
+
+  SurfaceQuad quad;
+  quad.set_size(io_surface_size_, pixel_io_surface_size_);
 
   glMatrixMode(GL_PROJECTION);
   glLoadIdentity();
 
   // Note that the projection keeps things in view units, so the use of
   // window_size / io_surface_size_ (as opposed to the pixel_ variants) below is
   // correct.
   glOrtho(0, window_size.width(), window_size.height(), 0, -1, 1);
   glMatrixMode(GL_MODELVIEW);
   glLoadIdentity();
 
   glDisable(GL_DEPTH_TEST);
   glDisable(GL_BLEND);
 
   if (has_io_surface) {
     context_->shader_program_cache()->UseBlitProgram();
     glActiveTexture(GL_TEXTURE0);
     glBindTexture(GL_TEXTURE_RECTANGLE_ARB, texture_);
 
-    DrawQuad(quad_);
+    DrawQuad(quad);
 
     glBindTexture(GL_TEXTURE_RECTANGLE_ARB, 0); CHECK_GL_ERROR();
 
     // Fill the resize gutters with white.
     if (window_size.width() > io_surface_size_.width() ||
         window_size.height() > io_surface_size_.height()) {
       context_->shader_program_cache()->UseSolidWhiteProgram();
       SurfaceQuad filler_quad;
       if (window_size.width() > io_surface_size_.width()) {
         // Draw right-side gutter down to the bottom of the window.
@@ skipping 624 matching lines @@
 }
 
 gfx::Rect CompositingIOSurfaceMac::IntersectWithIOSurface(
     const gfx::Rect& rect, float scale_factor) const {
   return gfx::IntersectRects(rect,
       gfx::ToEnclosingRect(gfx::ScaleRect(gfx::Rect(io_surface_size_),
                                           scale_factor)));
 }
 
 }  // namespace content