Only support left/right maximizing at 50% width when the --ash-enable-alternate-caption-button

ash/wm/workspace/snap_sizer.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 "ash/wm/workspace/snap_sizer.h"
 
 #include <cmath>
 
+#include "ash/ash_switches.h"
 #include "ash/screen_ash.h"
 #include "ash/wm/property_util.h"
 #include "ash/wm/window_resizer.h"
 #include "ash/wm/window_util.h"
 #include "ui/aura/window.h"
 #include "ui/aura/window_delegate.h"
 #include "ui/gfx/screen.h"
 
 namespace ash {
 namespace internal {
@@ skipping 36 matching lines @@
 int GetMaxWidth(aura::Window* window) {
   gfx::Rect work_area(ScreenAsh::GetDisplayWorkAreaBoundsInParent(window));
   return std::max(work_area.width() * kMaximumScreenPercent / 100,
                   GetMinWidth(window));
 }
 
 // Returns the width that |window| should be snapped to if resizing is disabled
 // in the SnapSizer.
 int GetDefaultWidth(aura::Window* window) {
   gfx::Rect work_area(ScreenAsh::GetDisplayWorkAreaBoundsInParent(window));
-  int width = std::max(kDefaultWidthSmallScreen, work_area.width() / 2);
+
+  int width = 0;
+  if (ash::switches::UseAlternateFrameCaptionButtonStyle()) {
+    // Only the 'half of screen' width is supported when using the alternate
+    // visual style for the frame caption buttons (minimize, maximize, restore,
+    // and close).
+    width = work_area.width() / 2;
+  } else {
+    width = std::max(kDefaultWidthSmallScreen, work_area.width() / 2);
+  }
 
   width = std::min(width, GetMaxWidth(window));
   return std::max(width, GetMinWidth(window));
 }
 
 // Create the list of possible widths for the current screen configuration:
 // Fill the |usable_width_| list with items from |kIdealWidth| which fit on
 // the screen and supplement it with the 'half of screen' size. Furthermore,
 // add an entry for 90% of the screen size if it is smaller than the biggest
 // value in the |kIdealWidth| list (to get a step between the values).
 std::vector<int> BuildIdealWidthList(aura::Window* window) {
+  if (ash::switches::UseAlternateFrameCaptionButtonStyle()) {
+    // Only the 'half of screen' width is supported when using the alternate
+    // visual style for the frame caption buttons (minimize, maximize,
+    // restore, and close).

[varkha, 2013/09/09 15:47:55]

nit: Instead of repeating the comment maybe just refer to see the comment above
in GetDefaultWidth.

[pkotwicz, 2013/09/10 18:22:32]

I do not think that this comment is long enough (alternatively that "See comment
for GetDefaultWidth() is short enough) to validate this change.

+    return std::vector<int>(1u, GetDefaultWidth(window));
+  }
+
   int minimum_width = GetMinWidth(window);
   int maximum_width = GetMaxWidth(window);
 
   gfx::Rect work_area(ScreenAsh::GetDisplayWorkAreaBoundsInParent(window));
   int half_width = work_area.width() / 2;
   if (half_width < minimum_width || half_width > maximum_width)
     half_width = 0;
 
   std::vector<int> ideal_width_list;
   for (size_t i = 0; i < arraysize(kIdealWidth); i++) {
@@ skipping 168 matching lines @@
   return GetTargetBoundsForSize(size_index_);
 }
 
 bool SnapSizer::AlongEdge(int x) const {
   gfx::Rect area(ScreenAsh::GetDisplayBoundsInParent(window_));
   return (x <= area.x()) || (x >= area.right() - 1);
 }
 
 }  // namespace internal
 }  // namespace ash