From 9513b53050196f98abba51b1db631ead7285da9d Mon Sep 17 00:00:00 2001
From: "mrbkap@gmail.com" <mrbkap@gmail.com>
Date: Sat, 22 Sep 2007 14:06:58 -0700
Subject: [PATCH] Restore the right caret in all cases. bug 395888, r+sr+a=roc

---
 .../libeditor/text/nsEditorEventListeners.cpp | 29 +++++++------------
 .../libeditor/text/nsEditorEventListeners.h   |  1 -
 layout/base/nsIPresShell.h                    | 16 ++++++----
 layout/base/nsPresShell.cpp                   | 15 ++++++----
 4 files changed, 32 insertions(+), 29 deletions(-)

diff --git a/editor/libeditor/text/nsEditorEventListeners.cpp b/editor/libeditor/text/nsEditorEventListeners.cpp
index b9bfdeefff22..681bf85290d1 100644
--- a/editor/libeditor/text/nsEditorEventListeners.cpp
+++ b/editor/libeditor/text/nsEditorEventListeners.cpp
@@ -524,25 +524,21 @@ nsresult
 nsTextEditorDragListener::DragEnter(nsIDOMEvent* aDragEvent)
 {
   nsCOMPtr<nsIPresShell> presShell = do_QueryReferent(mPresShell);
+  if (!presShell)
+    return NS_OK;
+
   if (!mCaret)
   {
-    if (presShell)
+    mCaret = do_CreateInstance("@mozilla.org/layout/caret;1");
+    if (mCaret)
     {
-      mCaret = do_CreateInstance("@mozilla.org/layout/caret;1");
-      if (mCaret)
-      {
-        mCaret->Init(presShell);
-        mCaret->SetCaretReadOnly(PR_TRUE);
-
-        mOtherCaret = presShell->SetCaret(mCaret);
-      }
-      mCaretDrawn = PR_FALSE;
+      mCaret->Init(presShell);
+      mCaret->SetCaretReadOnly(PR_TRUE);
     }
+    mCaretDrawn = PR_FALSE;
   }
-  else if (presShell)
-  {
-    presShell->SetCaret(mCaret);
-  }
+
+  presShell->SetCaret(mCaret);
 
   return DragOver(aDragEvent);
 }
@@ -644,11 +640,8 @@ nsTextEditorDragListener::DragDrop(nsIDOMEvent* aMouseEvent)
     nsCOMPtr<nsIPresShell> presShell = do_QueryReferent(mPresShell);
     if (presShell)
     {
-      NS_ASSERTION(mOtherCaret, "Where'd my other caret go?");
-      mCaret = presShell->SetCaret(mOtherCaret);
+      presShell->RestoreCaret();
     }
-
-    mOtherCaret = mCaret = nsnull;
   }
 
   if (!mEditor)
diff --git a/editor/libeditor/text/nsEditorEventListeners.h b/editor/libeditor/text/nsEditorEventListeners.h
index 63accc648ca0..8b4c1d95a8c1 100644
--- a/editor/libeditor/text/nsEditorEventListeners.h
+++ b/editor/libeditor/text/nsEditorEventListeners.h
@@ -237,7 +237,6 @@ protected:
   nsWeakPtr  mPresShell;
   
   nsCOMPtr<nsICaret> mCaret;
-  nsCOMPtr<nsICaret> mOtherCaret;
   PRBool             mCaretDrawn;
 };
 
diff --git a/layout/base/nsIPresShell.h b/layout/base/nsIPresShell.h
index 2068157f3b28..72011ea894de 100644
--- a/layout/base/nsIPresShell.h
+++ b/layout/base/nsIPresShell.h
@@ -102,10 +102,10 @@ class gfxContext;
 typedef short SelectionType;
 typedef PRUint32 nsFrameState;
 
-// D93B931B-D5EF-4D3C-AB99-444176963464
+// 4BE324F2-FB22-47CD-A653-19C70EE55E3F
 #define NS_IPRESSHELL_IID \
-{ 0xd93b931b, 0xd5ef, 0x4d3c, \
-  { 0xab, 0x99, 0x44, 0x41, 0x76, 0x96, 0x34, 0x64 } }
+{ 0x4BE324F2, 0xFB22, 0x47CD, \
+  { 0xA6, 0x53, 0x19, 0xC7, 0x0E, 0xE5, 0x5E, 0x3F } }
 
 // Constants for ScrollContentIntoView() function
 #define NS_PRESSHELL_SCROLL_TOP      0
@@ -495,9 +495,15 @@ public:
   NS_IMETHOD_(void) MaybeInvalidateCaretPosition() = 0;
 
   /**
-   * Set the current caret to a new caret. Returns the old caret.
+   * Set the current caret to a new caret. To undo this, call RestoreCaret.
    */
-  virtual already_AddRefed<nsICaret> SetCaret(nsICaret *aNewCaret) = 0;
+  virtual void SetCaret(nsICaret *aNewCaret) = 0;
+
+  /**
+   * Restore the caret to the original caret that this pres shell was created
+   * with.
+   */
+  virtual void RestoreCaret() = 0;
 
   /**
    * Should the images have borders etc.  Actual visual effects are determined
diff --git a/layout/base/nsPresShell.cpp b/layout/base/nsPresShell.cpp
index a54235c6cc2f..28ffbc77b24b 100644
--- a/layout/base/nsPresShell.cpp
+++ b/layout/base/nsPresShell.cpp
@@ -917,7 +917,8 @@ public:
   NS_IMETHOD SetCaretReadOnly(PRBool aReadOnly);
   NS_IMETHOD GetCaretEnabled(PRBool *aOutEnabled);
   NS_IMETHOD SetCaretVisibilityDuringSelection(PRBool aVisibility);
-  virtual already_AddRefed<nsICaret> SetCaret(nsICaret *aNewCaret);
+  virtual void SetCaret(nsICaret *aNewCaret);
+  virtual void RestoreCaret();
 
   NS_IMETHOD SetSelectionFlags(PRInt16 aInEnable);
   NS_IMETHOD GetSelectionFlags(PRInt16 *aOutEnable);
@@ -1130,6 +1131,7 @@ protected:
   nsCOMArray<nsIContent> mCurrentEventContentStack;
 
   nsCOMPtr<nsICaret>            mCaret;
+  nsCOMPtr<nsICaret>            mOriginalCaret;
   PRInt16                       mSelectionFlags;
   FrameArena                    mFrameArena;
   StackArena                    mStackArena;
@@ -1498,6 +1500,7 @@ PresShell::Init(nsIDocument* aDocument,
   if (NS_SUCCEEDED(err))
   {
     mCaret->Init(this);
+    mOriginalCaret = mCaret;
   }
 
   //SetCaretEnabled(PR_TRUE);       // make it show in browser windows
@@ -2616,12 +2619,14 @@ NS_IMETHODIMP_(void) PresShell::MaybeInvalidateCaretPosition()
   }
 }
 
-already_AddRefed<nsICaret> PresShell::SetCaret(nsICaret *aNewCaret)
+void PresShell::SetCaret(nsICaret *aNewCaret)
 {
-  nsICaret *oldCaret = nsnull;
-  mCaret.swap(oldCaret);
   mCaret = aNewCaret;
-  return oldCaret;
+}
+
+void PresShell::RestoreCaret()
+{
+  mCaret = mOriginalCaret;
 }
 
 NS_IMETHODIMP PresShell::SetCaretEnabled(PRBool aInEnable)