Refactoring the ownership of ui::InputMethod.

ash/magnifier/magnification_controller.cc

Index: ash/magnifier/magnification_controller.cc
diff --git a/ash/magnifier/magnification_controller.cc b/ash/magnifier/magnification_controller.cc
index a6ad0a1a1ad601877d8aa578781503fb3acfbffa..f7cc8b1c1ce6036c5fdc4548ef75432569d2a243 100644
--- a/ash/magnifier/magnification_controller.cc
+++ b/ash/magnifier/magnification_controller.cc
@@ -62,6 +62,12 @@ void MoveCursorTo(aura::WindowTreeHost* host, const gfx::Point& root_location) {
       gfx::ToCeiledPoint(host_location_3f.AsPointF()));
 }
 
+ui::InputMethod* GetInputMethod(aura::Window* root_window) {
+  if (root_window->GetHost())
+    return root_window->GetHost()->GetInputMethod();
+  return NULL;

[James Cook, 2015/06/01 22:20:59]

nullptr

[Shu Chen, 2015/06/02 04:11:16]

Done.

+}
+
 }  // namespace
 
 namespace ash {
@@ -205,8 +211,6 @@ class MagnificationControllerImpl : virtual public MagnificationController,
 
   ScrollDirection scroll_direction_;
 
-  ui::InputMethod* input_method_;  // Not owned.
-
   DISALLOW_COPY_AND_ASSIGN(MagnificationControllerImpl);
 };
 
@@ -219,16 +223,16 @@ MagnificationControllerImpl::MagnificationControllerImpl()
       is_enabled_(false),
       move_cursor_after_animation_(false),
       scale_(kNonMagnifiedScale),
-      scroll_direction_(SCROLL_NONE),
-      input_method_(NULL) {
+      scroll_direction_(SCROLL_NONE) {
   Shell::GetInstance()->AddPreTargetHandler(this);
   root_window_->AddObserver(this);
   point_of_interest_ = root_window_->bounds().CenterPoint();
 }
 
 MagnificationControllerImpl::~MagnificationControllerImpl() {
-  if (input_method_)
-    input_method_->RemoveObserver(this);
+  ui::InputMethod* input_method = GetInputMethod(root_window_);
+  if (input_method)
+    input_method->RemoveObserver(this);
 
   root_window_->RemoveObserver(this);
 
@@ -529,13 +533,10 @@ void MagnificationControllerImpl::SetScrollDirection(
 
 void MagnificationControllerImpl::SetEnabled(bool enabled) {
   Shell* shell = Shell::GetInstance();
+  ui::InputMethod* input_method = GetInputMethod(root_window_);
   if (enabled) {
-    if (!input_method_) {
-      input_method_ =
-          root_window_->GetProperty(aura::client::kRootWindowInputMethodKey);
-      if (input_method_)
-        input_method_->AddObserver(this);
-    }
+    if (!is_enabled_ && input_method)
+      input_method->AddObserver(this);
 
     float scale =
         Shell::GetInstance()->accessibility_delegate()->
@@ -556,10 +557,8 @@ void MagnificationControllerImpl::SetEnabled(bool enabled) {
     if (!is_enabled_)
       return;
 
-    if (input_method_) {
-      input_method_->RemoveObserver(this);
-      input_method_ = NULL;
-    }
+    if (input_method)
+      input_method->RemoveObserver(this);
 
     RedrawKeepingMousePosition(kNonMagnifiedScale, true);
     is_enabled_ = enabled;