mac: Use ScopedCGContextSaveGState in a few more places

chrome/browser/ui/cocoa/tabpose_window.mm

Index: chrome/browser/ui/cocoa/tabpose_window.mm
diff --git a/chrome/browser/ui/cocoa/tabpose_window.mm b/chrome/browser/ui/cocoa/tabpose_window.mm
index 796c7127d2feab4a3a6d134bbfacdbfed6830714..056519ab0c0fcd8f676c432daf3b86c62a397b17 100644
--- a/chrome/browser/ui/cocoa/tabpose_window.mm
+++ b/chrome/browser/ui/cocoa/tabpose_window.mm
@@ -330,7 +330,7 @@ void ThumbnailLoader::LoadThumbnail() {
     rwh->CopyFromBackingStoreToCGContext(destRect, context);
   } else if (thumbnail_) {
     // No cache hit, but the renderer returned a thumbnail to us.
-    gfx::ScopedCGContextSaveGState CGContextSaveGState(context);
+    gfx::ScopedCGContextSaveGState save_gstate(context);
     CGContextSetInterpolationQuality(context, kCGInterpolationHigh);
     CGContextDrawImage(context, destRect, thumbnail_.get());
   }