Bug 276431 helper-patch: Make args to imgIContainer::Draw const. r=joe

modules/libpr0n/public/imgIContainer.idl

@@ -71,7 +71,7 @@ native gfxGraphicsFilter(gfxPattern::GraphicsFilter);
  *
  * Internally, imgIContainer also manages animation of images.
  */
-[scriptable, uuid(e80ec20d-8e9c-405f-a673-cea00aa95b4d)]
+[scriptable, uuid(e6984403-1253-48fa-8a16-a350f76ab6c9)]
 interface imgIContainer : nsISupports
 {
   /**
@@ -171,9 +171,12 @@ interface imgIContainer : nsISupports
    *                  sample from.
    * @param aFlags Flags of the FLAG_* variety
    */
-  [noscript] void draw(in gfxContext aContext, in gfxGraphicsFilter aFilter,
-                       in gfxMatrix aUserSpaceToImageSpace, in gfxRect aFill,
-                       in nsIntRect aSubimage, in PRUint32 aFlags);
+  [noscript] void draw(in gfxContext aContext,
+                       in gfxGraphicsFilter aFilter,
+                       [const] in gfxMatrix aUserSpaceToImageSpace,
+                       [const] in gfxRect aFill,
+                       [const] in nsIntRect aSubimage,
+                       in PRUint32 aFlags);
 
   /*
    * Ensures that an image is decoding. Calling this function guarantees that

modules/libpr0n/src/imgContainer.cpp

@@ -2370,12 +2370,18 @@ imgContainer::SyncDecode()
 }
 
 //******************************************************************************
-/* [noscript] void draw(in gfxContext aContext, in gfxGraphicsFilter aFilter,
- * in gfxMatrix aUserSpaceToImageSpace, in gfxRect aFill, in nsIntRect aSubimage,
- * in PRUint32 aFlags); */ 
-NS_IMETHODIMP imgContainer::Draw(gfxContext *aContext, gfxPattern::GraphicsFilter aFilter, 
-                                 gfxMatrix &aUserSpaceToImageSpace, gfxRect &aFill,
-                                 nsIntRect &aSubimage, PRUint32 aFlags)
+/* [noscript] void draw(in gfxContext aContext,
+ *                      in gfxGraphicsFilter aFilter,
+ *                      [const] in gfxMatrix aUserSpaceToImageSpace,
+ *                      [const] in gfxRect aFill,
+ *                      [const] in nsIntRect aSubimage,
+ *                      in PRUint32 aFlags); */
+NS_IMETHODIMP imgContainer::Draw(gfxContext *aContext,
+                                 gfxPattern::GraphicsFilter aFilter,
+                                 const gfxMatrix &aUserSpaceToImageSpace,
+                                 const gfxRect &aFill,
+                                 const nsIntRect &aSubimage,
+                                 PRUint32 aFlags)
 {
   if (mError)
     return NS_ERROR_FAILURE;