Fix 117074: Panels [WIN]: Crash data shows a stack trace consistently involving PanelManager

The fix is not to involve PanelManager when it is not needed on the balloon notification code.

BUG=117074
TEST=Manual test to verify PanelManager is not involved on start.


Review URL: http://codereview.chromium.org/9621020

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@125679 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 17 insertions, 0 deletions

diff --git a/chrome/browser/notifications/balloon_collection_impl.cc b/chrome/browser/notifications/balloon_collection_impl.cc
index ec95f8e..cfeeac6 100644
--- a/chrome/browser/notifications/balloon_collection_impl.cc
+++ b/chrome/browser/notifications/balloon_collection_impl.cc
@@ -186,6 +186,7 @@ void BalloonCollectionImpl::Observe(
       // Fall through.
     case chrome::NOTIFICATION_PANEL_ADDED:
     case chrome::NOTIFICATION_PANEL_CLOSED:
+      layout_.enable_computing_panel_offset();
       if (layout_.ComputeOffsetToMoveAbovePanels(bounds))
         PositionBalloons(true);
       break;
@@ -275,6 +276,7 @@ void BalloonCollectionImpl::HandleMouseMoveEvent() {
 
 BalloonCollectionImpl::Layout::Layout()
     : placement_(INVALID),
+      need_to_compute_panel_offset_(false),
       offset_to_move_above_panels_(0) {
   RefreshSystemMetrics();
 }
@@ -406,6 +408,13 @@ gfx::Size BalloonCollectionImpl::Layout::ConstrainToSizeLimits(
 
 bool BalloonCollectionImpl::Layout::ComputeOffsetToMoveAbovePanels(
     const gfx::Rect& panel_bounds) {
+  // If the offset is not enabled due to that we have not received a
+  // notification about panel, don't proceed because we don't want to call
+  // PanelManager::GetInstance() to create an instance when panel is not
+  // present.
+  if (!need_to_compute_panel_offset_)
+    return false;
+
   const DockedPanelStrip::Panels& panels =
       PanelManager::GetInstance()->docked_strip()->panels();
   int offset_to_move_above_panels = 0;
diff --git a/chrome/browser/notifications/balloon_collection_impl.h b/chrome/browser/notifications/balloon_collection_impl.h
index 749c9e0..f505463 100644
--- a/chrome/browser/notifications/balloon_collection_impl.h
+++ b/chrome/browser/notifications/balloon_collection_impl.h
@@ -143,6 +143,10 @@ class BalloonCollectionImpl : public BalloonCollection,
     // to be repositioned.
     bool ComputeOffsetToMoveAbovePanels(const gfx::Rect& panel_bounds);
 
+    void enable_computing_panel_offset() {
+      need_to_compute_panel_offset_ = true;
+    }
+
    private:
     // Layout parameters
     int VerticalEdgeMargin() const;
@@ -161,6 +165,10 @@ class BalloonCollectionImpl : public BalloonCollection,
     Placement placement_;
     gfx::Rect work_area_;
 
+    // The flag that indicates that the panel offset computation should be
+    // performed.
+    bool need_to_compute_panel_offset_;
+
     // The offset that guarantees that the notificaitions shown in the
     // lower-right or lower-left corner of the screen will go above currently
     // shown panels and will not be obscured by them.