[Mac] Placate Clang's (pedantic) warning about CrTrackingArea's initializer.

chrome/browser/ui/cocoa/tracking_area.mm

Index: chrome/browser/ui/cocoa/tracking_area.mm
diff --git a/chrome/browser/ui/cocoa/tracking_area.mm b/chrome/browser/ui/cocoa/tracking_area.mm
index 692515fdbeca4a391dd7f63dd14db7b86fc79641..cd3e9ed7530e6bd86047b90da328f8711168dcfb 100644
--- a/chrome/browser/ui/cocoa/tracking_area.mm
+++ b/chrome/browser/ui/cocoa/tracking_area.mm
@@ -69,7 +69,7 @@
 
 - (id)initWithRect:(NSRect)rect
            options:(NSTrackingAreaOptions)options
-             owner:(id)owner
+      proxiedOwner:(id)owner
           userInfo:(NSDictionary*)userInfo {
   scoped_nsobject<CrTrackingAreaOwnerProxy> ownerProxy(
       [[CrTrackingAreaOwnerProxy alloc] initWithOwner:owner]);
@@ -82,6 +82,15 @@
   return self;
 }
 
+- (NSTrackingArea*)initWithRect:(NSRect)rect
+                        options:(NSTrackingAreaOptions)options
+                          owner:(id)owner
+                       userInfo:(NSDictionary*)userInfo {
+  [NSException raise:@"org.chromium.CrTrackingArea"
+      format:@"Cannot init a CrTrackingArea with NSTrackingArea's initializer"];
+  return nil;
+}
+
 - (void)dealloc {
   [[NSNotificationCenter defaultCenter] removeObserver:self];
   [super dealloc];