From 327addc38ab76901467230fad4577b3ddd9e8938 Mon Sep 17 00:00:00 2001
From: "Olli.Pettay%helsinki.fi" <Olli.Pettay%helsinki.fi>
Date: Sat, 22 Sep 2007 15:57:03 +0000
Subject: [PATCH] Bug 396652, gecko scrolls on activate event (mouse click)
 with gtk embeds, r+sr+a=roc, p=iainnicol-mozbugs2007@yahoo.co.uk+me

---
 content/events/src/nsEventStateManager.cpp    | 19 +++--------
 .../xul/content/src/nsXULPopupListener.cpp    | 14 ++------
 dom/public/base/nsIFocusController.h          | 33 +++++++++++++++++++
 3 files changed, 40 insertions(+), 26 deletions(-)

diff --git a/content/events/src/nsEventStateManager.cpp b/content/events/src/nsEventStateManager.cpp
index 94c64186e2d..2cd1b14bcb5 100644
--- a/content/events/src/nsEventStateManager.cpp
+++ b/content/events/src/nsEventStateManager.cpp
@@ -1091,13 +1091,14 @@ nsEventStateManager::PreHandleEvent(nsPresContext* aPresContext,
         win->GetRootFocusController();
       nsCOMPtr<nsIDOMElement> focusedElement;
       nsCOMPtr<nsIDOMWindowInternal> focusedWindow;
+      nsFocusScrollSuppressor scrollSuppressor;
 
       if (focusController) {
         // Obtain focus info from the focus controller.
         focusController->GetFocusedWindow(getter_AddRefs(focusedWindow));
         focusController->GetFocusedElement(getter_AddRefs(focusedElement));
 
-        focusController->SetSuppressFocusScroll(PR_TRUE);
+        scrollSuppressor.Init(focusController);
         focusController->SetActive(PR_TRUE);
       }
 
@@ -1151,7 +1152,6 @@ nsEventStateManager::PreHandleEvent(nsPresContext* aPresContext,
 
           focusController->GetSuppressFocus(&isSuppressed);
         }
-        focusController->SetSuppressFocusScroll(PR_FALSE);
       }
     }
     break;
@@ -3197,13 +3197,9 @@ nsEventStateManager::ChangeFocusWith(nsIContent* aFocusContent,
 
   // If this is called from mouse event, we lock to scroll.
   // Because the part of element is always in view. See bug 105894.
-  PRBool suppressFocusScroll =
-    focusController && (aFocusedWith == eEventFocusedByMouse);
-  if (suppressFocusScroll) {
-    PRBool currentState = PR_FALSE;
-    focusController->GetSuppressFocusScroll(&currentState);
-    NS_ASSERTION(!currentState, "locked scroll already!");
-    focusController->SetSuppressFocusScroll(PR_TRUE);
+  nsFocusScrollSuppressor scrollSuppressor;
+  if (aFocusedWith == eEventFocusedByMouse) {
+    scrollSuppressor.Init(focusController);
   }
 
   aFocusContent->SetFocus(mPresContext);
@@ -3225,11 +3221,6 @@ nsEventStateManager::ChangeFocusWith(nsIContent* aFocusContent,
       }
     }
   }
-
-  // Unlock scroll
-  if (suppressFocusScroll)
-    focusController->SetSuppressFocusScroll(PR_FALSE);
-
   return NS_OK;
 }
 
diff --git a/content/xul/content/src/nsXULPopupListener.cpp b/content/xul/content/src/nsXULPopupListener.cpp
index 3ff35a52343..77e12ffb73e 100644
--- a/content/xul/content/src/nsXULPopupListener.cpp
+++ b/content/xul/content/src/nsXULPopupListener.cpp
@@ -294,23 +294,13 @@ nsXULPopupListener::FireFocusOnTargetContent(nsIDOMNode* aTargetNode)
 
     if (focusableContent) {
       // Lock to scroll by SetFocus. See bug 309075.
-      nsCOMPtr<nsIFocusController> focusController = nsnull;
-      PRBool isAlreadySuppressed = PR_FALSE;
+      nsFocusScrollSuppressor scrollSuppressor;
       nsPIDOMWindow *ourWindow = doc->GetWindow();
       if (ourWindow) {
-        focusController = ourWindow->GetRootFocusController();
-        if (focusController) {
-          focusController->GetSuppressFocusScroll(&isAlreadySuppressed);
-          if (!isAlreadySuppressed)
-            focusController->SetSuppressFocusScroll(PR_TRUE);
-        }
+        scrollSuppressor.Init(ourWindow->GetRootFocusController());
       }
 
       focusableContent->SetFocus(context);
-
-      // Unlock scroll if it's needed.
-      if (focusController && !isAlreadySuppressed)
-        focusController->SetSuppressFocusScroll(PR_FALSE);
     } else if (!suppressBlur)
       esm->SetContentState(nsnull, NS_EVENT_STATE_FOCUS);
 
diff --git a/dom/public/base/nsIFocusController.h b/dom/public/base/nsIFocusController.h
index b8b930a833d..6670a746a2f 100644
--- a/dom/public/base/nsIFocusController.h
+++ b/dom/public/base/nsIFocusController.h
@@ -130,4 +130,37 @@ private:
   const char *mReason;
 };
 
+class nsFocusScrollSuppressor
+{
+public:
+  nsFocusScrollSuppressor(nsIFocusController* aController = nsnull)
+  : mWasSuppressed(PR_FALSE)
+  {
+    Init(aController);
+  }
+
+  ~nsFocusScrollSuppressor()
+  {
+    Init(nsnull);
+  }
+
+  void Init(nsIFocusController* aController)
+  {
+    if (mController) {
+      mController->SetSuppressFocusScroll(mWasSuppressed);
+    }
+
+    mController = aController;
+    if (mController) {
+      mController->GetSuppressFocusScroll(&mWasSuppressed);
+      if (!mWasSuppressed) {
+        mController->SetSuppressFocusScroll(PR_TRUE);
+      }
+    }
+  }
+private:
+  nsCOMPtr<nsIFocusController> mController;
+  PRBool                       mWasSuppressed;
+};
+
 #endif // nsIFocusController_h__