Part of fix for 42418, patch up event target from PresShell after re-entrant events to avoid null targets. r:nisheeth

content/events/src/nsEventStateManager.cpp

@@ -2054,6 +2054,14 @@ nsEventStateManager::GetEventTarget(nsIFrame **aFrame)
     }
   }
 
+  if (!mCurrentTarget) {
+	  nsCOMPtr<nsIPresShell> presShell;
+	  mPresContext->GetShell(getter_AddRefs(presShell));
+	  if (presShell) {
+	    presShell->GetEventTargetFrame(&mCurrentTarget);
+	  }
+  }
+
   *aFrame = mCurrentTarget;
   return NS_OK;
 }
@@ -2074,7 +2082,15 @@ nsEventStateManager::GetEventTargetContent(nsEvent* aEvent, nsIContent** aConten
     NS_IF_ADDREF(*aContent);
     return NS_OK;      
   }
-  
+
+  if (!mCurrentTarget) {
+	  nsCOMPtr<nsIPresShell> presShell;
+	  mPresContext->GetShell(getter_AddRefs(presShell));
+	  if (presShell) {
+	    presShell->GetEventTargetFrame(&mCurrentTarget);
+	  }
+  }
+
   if (mCurrentTarget) {
     mCurrentTarget->GetContentForEvent(mPresContext, aEvent, aContent);
     return NS_OK;

layout/base/nsIPresShell.h

@@ -386,6 +386,11 @@ public:
                                    nsIContent* aContent, 
                                    nsEventStatus* aStatus) = 0;
 
+  /**
+    * Gets the current target event frame from the PresShell
+    */
+  NS_IMETHOD GetEventTargetFrame(nsIFrame** aFrame) = 0;
+
   /**
    * Get and set the history state for the current document 
    */

layout/base/nsPresShell.cpp

@@ -683,6 +683,7 @@ public:
                                          nsIContentIterator** aIterator) const;
  
   NS_IMETHOD HandleEventWithTarget(nsEvent* aEvent, nsIFrame* aFrame, nsIContent* aContent, nsEventStatus* aStatus);
+  NS_IMETHOD GetEventTargetFrame(nsIFrame** aFrame);
 
   NS_IMETHOD IsReflowLocked(PRBool* aIsLocked);  
 
@@ -3697,6 +3698,13 @@ PresShell::GetCurrentEventFrame()
   return mCurrentEventFrame;
 }
 
+NS_IMETHODIMP
+PresShell::GetEventTargetFrame(nsIFrame** aFrame)
+{
+	*aFrame = GetCurrentEventFrame();
+	return NS_OK;
+}
+
 void
 PresShell::PushCurrentEventInfo(nsIFrame* aFrame, nsIContent* aContent)
 {

layout/base/public/nsIPresShell.h

@@ -386,6 +386,11 @@ public:
                                    nsIContent* aContent, 
                                    nsEventStatus* aStatus) = 0;
 
+  /**
+    * Gets the current target event frame from the PresShell
+    */
+  NS_IMETHOD GetEventTargetFrame(nsIFrame** aFrame) = 0;
+
   /**
    * Get and set the history state for the current document 
    */

layout/events/src/nsEventStateManager.cpp

@@ -2054,6 +2054,14 @@ nsEventStateManager::GetEventTarget(nsIFrame **aFrame)
     }
   }
 
+  if (!mCurrentTarget) {
+	  nsCOMPtr<nsIPresShell> presShell;
+	  mPresContext->GetShell(getter_AddRefs(presShell));
+	  if (presShell) {
+	    presShell->GetEventTargetFrame(&mCurrentTarget);
+	  }
+  }
+
   *aFrame = mCurrentTarget;
   return NS_OK;
 }
@@ -2074,7 +2082,15 @@ nsEventStateManager::GetEventTargetContent(nsEvent* aEvent, nsIContent** aConten
     NS_IF_ADDREF(*aContent);
     return NS_OK;      
   }
-  
+
+  if (!mCurrentTarget) {
+	  nsCOMPtr<nsIPresShell> presShell;
+	  mPresContext->GetShell(getter_AddRefs(presShell));
+	  if (presShell) {
+	    presShell->GetEventTargetFrame(&mCurrentTarget);
+	  }
+  }
+
   if (mCurrentTarget) {
     mCurrentTarget->GetContentForEvent(mPresContext, aEvent, aContent);
     return NS_OK;

layout/html/base/src/nsPresShell.cpp

@@ -683,6 +683,7 @@ public:
                                          nsIContentIterator** aIterator) const;
  
   NS_IMETHOD HandleEventWithTarget(nsEvent* aEvent, nsIFrame* aFrame, nsIContent* aContent, nsEventStatus* aStatus);
+  NS_IMETHOD GetEventTargetFrame(nsIFrame** aFrame);
 
   NS_IMETHOD IsReflowLocked(PRBool* aIsLocked);  
 
@@ -3697,6 +3698,13 @@ PresShell::GetCurrentEventFrame()
   return mCurrentEventFrame;
 }
 
+NS_IMETHODIMP
+PresShell::GetEventTargetFrame(nsIFrame** aFrame)
+{
+	*aFrame = GetCurrentEventFrame();
+	return NS_OK;
+}
+
 void
 PresShell::PushCurrentEventInfo(nsIFrame* aFrame, nsIContent* aContent)
 {