Mac a11y: Fix AXTextMarker leaks.

content/browser/accessibility/browser_accessibility_cocoa.mm

Index: content/browser/accessibility/browser_accessibility_cocoa.mm
diff --git a/content/browser/accessibility/browser_accessibility_cocoa.mm b/content/browser/accessibility/browser_accessibility_cocoa.mm
index f0d696d97b18e355b41e42b15f5a19d65f944754..2698d30c785d5b46b8259a9346cfe8147a84e49c 100644
--- a/content/browser/accessibility/browser_accessibility_cocoa.mm
+++ b/content/browser/accessibility/browser_accessibility_cocoa.mm
@@ -140,25 +140,24 @@ AXTextMarkerRef AXTextMarkerRangeCopyEndMarker(
 
 }  // extern "C"
 
-// to call |release| on it to transfer ownership of the position to the text
-// marker object.
+// AXTextMarkerCreate copies from data buffer given to it.
 id CreateTextMarker(AXPlatformPositionInstance position) {
   AXTextMarkerRef text_marker = AXTextMarkerCreate(
-      kCFAllocatorDefault, reinterpret_cast<const UInt8*>(position.release()),
+      kCFAllocatorDefault, reinterpret_cast<const UInt8*>(position.get()),
       sizeof(AXPlatformPosition));
   return static_cast<id>(
       base::mac::CFTypeRefToNSObjectAutorelease(text_marker));
 }
 
-// |range| is destructed at the end of this method and ownership of its |anchor|
-// and |focus| are transfered to the marker range object.
+// |range| is destructed at the end of this method. |anchor| and |focus| are
+// copied into the individual text markers.
 id CreateTextMarkerRange(const AXPlatformRange range) {
-  AXTextMarkerRef start_marker = AXTextMarkerCreate(
+  base::ScopedCFTypeRef<AXTextMarkerRef> start_marker(AXTextMarkerCreate(
       kCFAllocatorDefault, reinterpret_cast<const UInt8*>(range.anchor()),
-      sizeof(AXPlatformPosition));
-  AXTextMarkerRef end_marker = AXTextMarkerCreate(
+      sizeof(AXPlatformPosition)));
+  base::ScopedCFTypeRef<AXTextMarkerRef> end_marker(AXTextMarkerCreate(
       kCFAllocatorDefault, reinterpret_cast<const UInt8*>(range.focus()),
-      sizeof(AXPlatformPosition));
+      sizeof(AXPlatformPosition)));
   AXTextMarkerRangeRef marker_range =
       AXTextMarkerRangeCreate(kCFAllocatorDefault, start_marker, end_marker);
   return static_cast<id>(