Ensure that the extension icons show up in the omnibox at fractional scales.

ui/base/layout.h

 // 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.
 
 #ifndef UI_BASE_LAYOUT_H_
 #define UI_BASE_LAYOUT_H_
 
 #include <vector>
 
 #include "build/build_config.h"
@@ skipping 36 matching lines @@
 // Converting from float to ScaleFactor is inefficient and should be done as
 // little as possible.
 UI_BASE_EXPORT ScaleFactor GetSupportedScaleFactor(float image_scale);
 
 // Returns the ScaleFactor used by |view|.
 UI_BASE_EXPORT float GetScaleFactorForNativeView(gfx::NativeView view);
 
 // Returns the image scale for the scale factor passed in.
 UI_BASE_EXPORT float GetScaleForScaleFactor(ScaleFactor scale_factor);
 
+// Returns true if the scale passed in is the list of supported scales for
+// the platform.
+UI_BASE_EXPORT bool IsSupportedScale(float scale);
+
 namespace test {
 // Class which changes the value of GetSupportedScaleFactors() to
 // |new_scale_factors| for the duration of its lifetime.
 class UI_BASE_EXPORT ScopedSetSupportedScaleFactors {
  public:
   explicit ScopedSetSupportedScaleFactors(
       const std::vector<ui::ScaleFactor>& new_scale_factors);
   ~ScopedSetSupportedScaleFactors();
 
  private:
   std::vector<ui::ScaleFactor>* original_scale_factors_;
 
   DISALLOW_COPY_AND_ASSIGN(ScopedSetSupportedScaleFactors);
 };
 
 }  // namespace test
 
 }  // namespace ui
 
 #endif  // UI_BASE_LAYOUT_H_