Don't return unsupported scales frrom GetScaleFactorFromScale()

ui/base/layout.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 "ui/base/layout.h"
 
 #include <algorithm>
 #include <cmath>
 #include <limits>
 
@@ skipping 95 matching lines @@
   return LAYOUT_DESKTOP;
 #else
   return LAYOUT_DESKTOP;
 #endif
 }
 
 ScaleFactor GetScaleFactorFromScale(float scale) {
   size_t closest_match = 0;
   float smallest_diff =  std::numeric_limits<float>::max();
   for (size_t i = 0; i < kScaleFactorScalesLength; ++i) {
+    if (!IsScaleFactorSupported(static_cast<ScaleFactor>(i)))

[pkotwicz, 2012/09/19 21:05:17]

Nit: iterate through the scale factors you get from GetSupportedScaleFactors()
rather than doing this, it is more efficient.

[Xianzhu, 2012/09/19 21:38:23]

Oops I should have made that kind of change :)

+      continue;
     float diff = std::abs(kScaleFactorScales[i] - scale);
     if (diff < smallest_diff) {
       closest_match = i;
       smallest_diff = diff;
     }
   }
-  return static_cast<ui::ScaleFactor>(closest_match);
+  return static_cast<ScaleFactor>(closest_match);
 }
 
 float GetScaleFactorScale(ScaleFactor scale_factor) {
   return kScaleFactorScales[scale_factor];
 }
 
 std::vector<ScaleFactor> GetSupportedScaleFactors() {
   return GetSupportedScaleFactorsInternal();
 }
 
@@ skipping 24 matching lines @@
   return GetScaleFactorFromScale(
       root_window->compositor()->device_scale_factor());
 #else
   NOTIMPLEMENTED();
   return SCALE_FACTOR_NONE;
 #endif
 }
 #endif  // !defined(OS_MACOSX)
 
 }  // namespace ui