[ash-md] Disables rounded corners by default in overview mode

ash/common/wm/overview/window_grid.cc

 // Copyright 2014 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/common/wm/overview/window_grid.h"
 
 #include <algorithm>
 #include <functional>
 #include <set>
 #include <utility>
@@ skipping 56 matching lines @@
 // fixed aspect ratio. The number of columns is determined by maximizing the
 // area of them based on the number of window_list.
 const float kCardAspectRatio = 4.0f / 3.0f;
 
 // The minimum number of cards along the major axis (i.e. horizontally on a
 // landscape orientation).
 const int kMinCardsMajor = 3;
 
 // Hiding window headers can be resource intensive. Only hide the headers when
 // the number of windows in this grid is less or equal than this number.
-const int kMaxWindowsCountToHideHeader = 10;
+// The default is 0, meaning that mask layers are never used and the bottom
+// corners are not rounded in overview.
+const int kMaxWindowsCountToHideHeaderWithMasks = 0;
 
 const int kOverviewSelectorTransitionMilliseconds = 250;
 
 // The color and opacity of the screen shield in overview.
 const SkColor kShieldColor = SkColorSetARGB(255, 0, 0, 0);
 const float kShieldOpacity = 0.7f;
 
 // The color and opacity of the overview selector.
 const SkColor kWindowSelectionColor = SkColorSetARGB(128, 0, 0, 0);
 const SkColor kWindowSelectionColorMD = SkColorSetARGB(51, 255, 255, 255);
@@ skipping 365 matching lines @@
 }
 
 void WindowGrid::PositionWindowsMD(bool animate) {
   if (window_list_.empty())
     return;
 
   const int kUnlimited = -1;
   const size_t windows_count = window_list_.size();
   const base::CommandLine* command_line =
       base::CommandLine::ForCurrentProcess();
-  int windows_to_use_masks = kMaxWindowsCountToHideHeader;
+  int windows_to_use_masks = kMaxWindowsCountToHideHeaderWithMasks;
   if (command_line->HasSwitch(switches::kAshMaxWindowsToUseMaskInOverview) &&
       (!base::StringToInt(command_line->GetSwitchValueASCII(
                               switches::kAshMaxWindowsToUseMaskInOverview),
                           &windows_to_use_masks) ||
        windows_to_use_masks <= kUnlimited)) {
-    windows_to_use_masks = kMaxWindowsCountToHideHeader;
+    windows_to_use_masks = kMaxWindowsCountToHideHeaderWithMasks;
   }
   int windows_to_use_shapes = kUnlimited;
   if (command_line->HasSwitch(switches::kAshMaxWindowsToUseShapeInOverview) &&
       (!base::StringToInt(command_line->GetSwitchValueASCII(
                               switches::kAshMaxWindowsToUseShapeInOverview),
                           &windows_to_use_shapes) ||
        windows_to_use_shapes <= kUnlimited)) {
     windows_to_use_shapes = kUnlimited;
   }
   WindowSelectorItem::set_use_mask(windows_to_use_masks <= kUnlimited ||
@@ skipping 534 matching lines @@
         *min_right = left;
       if (*max_right < left)
         *max_right = left;
     }
     *max_bottom = top + height;
   }
   return windows_fit;
 }
 
 }  // namespace ash