exo: Clean up cursor code

components/exo/pointer.cc

Index: components/exo/pointer.cc
diff --git a/components/exo/pointer.cc b/components/exo/pointer.cc
index a1778eb34cb1220669661032e29b3b587a0a0cc3..092501a46248c805c0403528c72492abcd7e9d73 100644
--- a/components/exo/pointer.cc
+++ b/components/exo/pointer.cc
@@ -119,7 +119,7 @@ void Pointer::SetCursor(Surface* surface, const gfx::Point& hotspot) {
   if (!cursor_changed)
     return;
 
-  // If |surface_| is set then ascynchrounsly capture a snapshot of cursor,
+  // If |surface_| is set then asynchronously capture a snapshot of cursor,
   // otherwise cancel pending capture and immediately set the cursor to "none".
   if (surface_) {
     CaptureCursor();
@@ -166,7 +166,10 @@ void Pointer::OnMouseEvent(ui::MouseEvent* event) {
     delegate_->OnPointerFrame();
   }
 
-  if (focus_ && event->IsMouseEvent() && event->type() != ui::ET_MOUSE_EXITED) {
+  if (!focus_)
+    return;
+
+  if (event->IsMouseEvent() && event->type() != ui::ET_MOUSE_EXITED) {
     // Generate motion event if location changed. We need to check location
     // here as mouse movement can generate both "moved" and "entered" events
     // but OnPointerMotion should only be called if location changed since
@@ -180,44 +183,39 @@ void Pointer::OnMouseEvent(ui::MouseEvent* event) {
 
   switch (event->type()) {
     case ui::ET_MOUSE_PRESSED:
-    case ui::ET_MOUSE_RELEASED:
-      if (focus_) {
-        delegate_->OnPointerButton(event->time_stamp(),
-                                   event->changed_button_flags(),
-                                   event->type() == ui::ET_MOUSE_PRESSED);
-        delegate_->OnPointerFrame();
-      }
+    case ui::ET_MOUSE_RELEASED: {
+      delegate_->OnPointerButton(event->time_stamp(),
+                                 event->changed_button_flags(),
+                                 event->type() == ui::ET_MOUSE_PRESSED);
+      delegate_->OnPointerFrame();
       break;
-    case ui::ET_SCROLL:
-      if (focus_) {
-        ui::ScrollEvent* scroll_event = static_cast<ui::ScrollEvent*>(event);
-        delegate_->OnPointerScroll(
-            event->time_stamp(),
-            gfx::Vector2dF(scroll_event->x_offset(), scroll_event->y_offset()),
-            false);
-        delegate_->OnPointerFrame();
-      }
+    }
+    case ui::ET_SCROLL: {
+      ui::ScrollEvent* scroll_event = static_cast<ui::ScrollEvent*>(event);
+      delegate_->OnPointerScroll(
+          event->time_stamp(),
+          gfx::Vector2dF(scroll_event->x_offset(), scroll_event->y_offset()),
+          false);
+      delegate_->OnPointerFrame();
       break;
-    case ui::ET_MOUSEWHEEL:
-      if (focus_) {
-        delegate_->OnPointerScroll(
-            event->time_stamp(),
-            static_cast<ui::MouseWheelEvent*>(event)->offset(), true);
-        delegate_->OnPointerFrame();
-      }
+    }
+    case ui::ET_MOUSEWHEEL: {
+      delegate_->OnPointerScroll(
+          event->time_stamp(),
+          static_cast<ui::MouseWheelEvent*>(event)->offset(), true);
+      delegate_->OnPointerFrame();
       break;
-    case ui::ET_SCROLL_FLING_START:
-      if (focus_) {
-        delegate_->OnPointerScrollStop(event->time_stamp());
-        delegate_->OnPointerFrame();
-      }
+    }
+    case ui::ET_SCROLL_FLING_START: {
+      delegate_->OnPointerScrollStop(event->time_stamp());
+      delegate_->OnPointerFrame();
       break;
-    case ui::ET_SCROLL_FLING_CANCEL:
-      if (focus_) {
-        delegate_->OnPointerScrollCancel(event->time_stamp());
-        delegate_->OnPointerFrame();
-      }
+    }
+    case ui::ET_SCROLL_FLING_CANCEL: {
+      delegate_->OnPointerScrollCancel(event->time_stamp());
+      delegate_->OnPointerFrame();
       break;
+    }
     case ui::ET_MOUSE_MOVED:
     case ui::ET_MOUSE_DRAGGED:
     case ui::ET_MOUSE_ENTERED:
@@ -229,14 +227,16 @@ void Pointer::OnMouseEvent(ui::MouseEvent* event) {
       break;
   }
 
-  if (focus_)
-    UpdateCursorScale();
+  UpdateCursorScale();
 }
 
 void Pointer::OnScrollEvent(ui::ScrollEvent* event) {
   OnMouseEvent(event);
 }
 
+////////////////////////////////////////////////////////////////////////////////
+// WMHelper::CursorObserver overrides:
+
 void Pointer::OnCursorSetChanged(ui::CursorSetType cursor_set) {
   if (focus_)
     UpdateCursorScale();
@@ -321,6 +321,7 @@ void Pointer::UpdateCursorScale() {
 
 void Pointer::CaptureCursor() {
   DCHECK(surface_);
+  DCHECK(focus_);
 
   // Set UI scale before submitting capture request.
   surface_->window()->layer()->SetTransform(