Bug 938612 - ensure the image buffers for canvases are freed; r=smaug

Landing this on a CLOSED TREE

content/canvas/src/CanvasRenderingContext2D.cpp

@@ -1084,9 +1084,9 @@ CanvasRenderingContext2D::GetInputStream(const char *aMimeType,
                                          const PRUnichar *aEncoderOptions,
                                          nsIInputStream **aStream)
 {
-  uint8_t* imageBuffer = nullptr;
+  nsAutoArrayPtr<uint8_t> imageBuffer;
   int32_t format = 0;
-  GetImageBuffer(&imageBuffer, &format);
+  GetImageBuffer(getter_Transfers(imageBuffer), &format);
   if (!imageBuffer) {
     return NS_ERROR_FAILURE;
   }

content/canvas/src/WebGLContext.cpp

@@ -794,9 +794,9 @@ WebGLContext::GetInputStream(const char* aMimeType,
     if (!gl)
         return NS_ERROR_FAILURE;
 
-    uint8_t* imageBuffer = nullptr;
+    nsAutoArrayPtr<uint8_t> imageBuffer;
     int32_t format = 0;
-    GetImageBuffer(&imageBuffer, &format);
+    GetImageBuffer(getter_Transfers(imageBuffer), &format);
     if (!imageBuffer) {
         return NS_ERROR_FAILURE;
     }