ash: Add accelerator for snapping windows left/right.

ash/wm/workspace/snap_sizer.cc

Index: ash/wm/workspace/snap_sizer.cc
diff --git a/ash/wm/workspace/snap_sizer.cc b/ash/wm/workspace/snap_sizer.cc
index 9b064e7bf1fdf08844999765fa30fb163e9d54d2..963742b49d7e24d7cca64284063b68ff282aa071 100644
--- a/ash/wm/workspace/snap_sizer.cc
+++ b/ash/wm/workspace/snap_sizer.cc
@@ -66,6 +66,15 @@ void SnapSizer::Update(const gfx::Point& location) {
   time_last_update_ = base::TimeTicks::Now();
 }
 
+gfx::Rect SnapSizer::GetSnapBounds(const gfx::Rect& bounds) {
+  for (size_t i = 0; i < arraysize(kPercents); ++i) {
+    gfx::Rect target = GetTargetBoundsForPercent(i);
+    if (target != bounds && target.width() > bounds.width())

[sky, 2012/04/25 19:23:20]

Can you use rect == to find the current snap bounds?

[sadrul, 2012/04/25 19:37:54]

Done.

+      return target;
+  }
+  return target_bounds_;
+}
+
 int SnapSizer::CalculateIncrement(int x, int reference_x) const {
   if (AlongEdge(x))
     return 1;
@@ -94,12 +103,16 @@ void SnapSizer::ChangeBounds(int x, int delta) {
 }
 
 gfx::Rect SnapSizer::GetTargetBounds() const {
+  return GetTargetBoundsForPercent(percent_index_);
+}
+
+gfx::Rect SnapSizer::GetTargetBoundsForPercent(int percent_index) const {
   gfx::Rect work_area(ScreenAsh::GetUnmaximizedWorkAreaBounds(window_));
   int y = WindowResizer::AlignToGridRoundUp(work_area.y(), grid_size_);
   // We don't align to the bottom of the grid as the launcher may not
   // necessarily align to the grid (happens when auto-hidden).
   int max_y = work_area.bottom();
-  int width = static_cast<float>(work_area.width()) * kPercents[percent_index_];
+  int width = static_cast<float>(work_area.width()) * kPercents[percent_index];
   if (edge_ == LEFT_EDGE) {
     int x = WindowResizer::AlignToGridRoundUp(work_area.x(), grid_size_);
     int mid_x = WindowResizer::AlignToGridRoundUp(