Cancel partial screenshot UI when lock happens.

ash/wm/partial_screenshot_event_filter.cc

Index: ash/wm/partial_screenshot_event_filter.cc
diff --git a/ash/wm/partial_screenshot_event_filter.cc b/ash/wm/partial_screenshot_event_filter.cc
index ce21e0070de487809367dd104161ca63cd6bcfa9..da0ff29899d4cb3d8ef9751ea8542be7859043b8 100644
--- a/ash/wm/partial_screenshot_event_filter.cc
+++ b/ash/wm/partial_screenshot_event_filter.cc
@@ -32,7 +32,7 @@ bool PartialScreenshotEventFilter::PreHandleKeyEvent(
   }
 
   if (event->key_code() == ui::VKEY_ESCAPE)
-    view_->Cancel();
+    Cancel();
 
   // Always handled: other windows shouldn't receive input while we're
   // taking a screenshot.
@@ -54,6 +54,19 @@ ui::GestureStatus PartialScreenshotEventFilter::PreHandleGestureEvent(
   return ui::GESTURE_STATUS_UNKNOWN;  // Not handled.
 }
 
+void PartialScreenshotEventFilter::OnLoginStateChange(bool logged_in,
+                                                      bool is_guest) {
+  Cancel();
+}
+
+void PartialScreenshotEventFilter::OnExit() {
+  Cancel();
+}
+
+void PartialScreenshotEventFilter::OnLockStateChange(bool locked) {
+  Cancel();
+}
+
 void PartialScreenshotEventFilter::Activate(PartialScreenshotView* view) {
   view_ = view;
 }
@@ -62,5 +75,9 @@ void PartialScreenshotEventFilter::Deactivate() {
   view_ = NULL;
 }
 
+void PartialScreenshotEventFilter::Cancel() {
+  if (view_)
+    view_->Cancel();
+}
 }  // namespace internal
 }  // namespace ash