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

ash/wm/workspace/workspace_window_resizer.cc

Index: ash/wm/workspace/workspace_window_resizer.cc
diff --git a/ash/wm/workspace/workspace_window_resizer.cc b/ash/wm/workspace/workspace_window_resizer.cc
index 4b8c0aaf7e9366f91aa1fd1bf6f8d88f9429b0c9..aaa69c7bfd24116ec932bf7ea2b71c25d988f744 100644
--- a/ash/wm/workspace/workspace_window_resizer.cc
+++ b/ash/wm/workspace/workspace_window_resizer.cc
@@ -422,8 +422,7 @@ void WorkspaceWindowResizer::CompleteDrag(int event_flags) {
                                initial_bounds :
                                details_.restore_bounds);
     }
-    window()->SetBounds(snap_sizer_->target_bounds());
-    return;
+    snap_sizer_->Snap();
   }
 }
 
@@ -855,9 +854,6 @@ void WorkspaceWindowResizer::UpdateSnapPhantomWindow(const gfx::Point& location,
   if (!did_move_or_resize_ || details_.window_component != HTCAPTION)
     return;
 
-  if (!wm::CanSnapWindow(window()))
-    return;
-
   if (window()->type() == aura::client::WINDOW_TYPE_PANEL &&
       window()->GetProperty(kPanelAttachedKey)) {
     return;
@@ -865,25 +861,26 @@ void WorkspaceWindowResizer::UpdateSnapPhantomWindow(const gfx::Point& location,
 
   SnapType last_type = snap_type_;
   snap_type_ = GetSnapType(location);
-  if (snap_type_ == SNAP_NONE || snap_type_ != last_type) {
+  using internal::SnapSizer;
+  SnapSizer::Edge edge = (snap_type_ == SNAP_LEFT_EDGE) ?
+      SnapSizer::LEFT_EDGE : SnapSizer::RIGHT_EDGE;
+  if (snap_type_ == SNAP_NONE ||
+      !SnapSizer::CanSnapWindow(window(), edge)) {
+    snap_type_ = SNAP_NONE;
     snap_phantom_window_controller_.reset();
     snap_sizer_.reset();
-    if (snap_type_ == SNAP_NONE)
-      return;
-  }
-  if (!snap_sizer_) {
-    SnapSizer::Edge edge = (snap_type_ == SNAP_LEFT_EDGE) ?
-        SnapSizer::LEFT_EDGE : SnapSizer::RIGHT_EDGE;
-    snap_sizer_.reset(new SnapSizer(window(),
-                                    location,
-                                    edge,
-                                    internal::SnapSizer::OTHER_INPUT));
-  } else {
-    snap_sizer_->Update(location);
+    return;
   }
-  if (!snap_phantom_window_controller_) {
+
+  if (snap_type_ != last_type ||

[varkha, 2013/08/30 17:13:25]

Will the animations be smoother if we don't re-create the snap-sizer and / or
snap_phantom_window_controller_ when alternating between left and right edges?

[pkotwicz, 2013/08/30 21:10:57]

I believe that you always transition through SNAP_NONE when alternating between
the left and right edges.

+      !snap_sizer_ ||
+      !snap_phantom_window_controller_) {
+    snap_sizer_.reset(
+        new SnapSizer(window(), location, edge, SnapSizer::STEP_YES));
     snap_phantom_window_controller_.reset(
         new PhantomWindowController(window()));
+  } else {
+    snap_sizer_->Update(location);
   }
   snap_phantom_window_controller_->Show(ScreenAsh::ConvertRectToScreen(
       window()->parent(), snap_sizer_->target_bounds()));