fix the notification continuous-resize problem by preventing scrollbars from being used until the maximum size is reached.

BUG=48494
TEST=create notifications of various sizes, watch for jitter

Review URL: http://codereview.chromium.org/2941003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@51978 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 18 insertions, 1 deletions

diff --git a/chrome/browser/notifications/balloon.h b/chrome/browser/notifications/balloon.h
index a60d9a9..87440c9 100644
--- a/chrome/browser/notifications/balloon.h
+++ b/chrome/browser/notifications/balloon.h
@@ -63,6 +63,11 @@ class Balloon {
   const gfx::Size& content_size() const { return content_size_; }
   void set_content_size(const gfx::Size& size) { content_size_ = size; }
 
+  const gfx::Size& min_scrollbar_size() const { return min_scrollbar_size_; }
+  void set_min_scrollbar_size(const gfx::Size& size) {
+    min_scrollbar_size_ = size;
+  }
+
   // Request a new content size for this balloon.  This will get passed
   // to the balloon collection for checking against available space and
   // min/max restrictions.
@@ -110,6 +115,9 @@ class Balloon {
   gfx::Point position_;
   gfx::Size content_size_;
 
+  // Smallest size for this balloon where scrollbars will be shown.
+  gfx::Size min_scrollbar_size_;
+
   DISALLOW_COPY_AND_ASSIGN(Balloon);
 };
 
diff --git a/chrome/browser/notifications/balloon_collection.cc b/chrome/browser/notifications/balloon_collection.cc
index 7a8302d..09bfb56d 100644
--- a/chrome/browser/notifications/balloon_collection.cc
+++ b/chrome/browser/notifications/balloon_collection.cc
@@ -7,6 +7,7 @@
 #include "base/logging.h"
 #include "base/stl_util-inl.h"
 #include "chrome/browser/notifications/balloon.h"
+#include "chrome/browser/notifications/balloon_host.h"
 #include "chrome/browser/notifications/notification.h"
 #include "chrome/browser/window_sizer.h"
 #include "gfx/rect.h"
@@ -41,9 +42,14 @@ BalloonCollectionImpl::~BalloonCollectionImpl() {
 void BalloonCollectionImpl::Add(const Notification& notification,
                                 Profile* profile) {
   Balloon* new_balloon = MakeBalloon(notification, profile);
-
+  // The +1 on width is necessary because width is fixed on notifications,
+  // so since we always have the max size, we would always hit the scrollbar
+  // condition.  We are only interested in comparing height to maximum.
+  new_balloon->set_min_scrollbar_size(gfx::Size(1 + layout_.max_balloon_width(),
+                                                layout_.max_balloon_height()));
   new_balloon->SetPosition(layout_.OffScreenLocation(), false);
   new_balloon->Show();
+
   balloons_.push_back(new_balloon);
   PositionBalloons(false);
 
diff --git a/chrome/browser/notifications/balloon_host.cc b/chrome/browser/notifications/balloon_host.cc
index f3190d5..e962f5a 100644
--- a/chrome/browser/notifications/balloon_host.cc
+++ b/chrome/browser/notifications/balloon_host.cc
@@ -58,6 +58,9 @@ void BalloonHost::Close(RenderViewHost* render_view_host) {
 }
 
 void BalloonHost::RenderViewCreated(RenderViewHost* render_view_host) {
+  render_view_host->Send(new ViewMsg_DisableScrollbarsForSmallWindows(
+      render_view_host->routing_id(), balloon_->min_scrollbar_size()));
+  render_view_host->WasResized();
   render_view_host->EnablePreferredSizeChangedMode(
       kPreferredSizeWidth | kPreferredSizeHeightThisIsSlow);
 }