Align superclasses for multiple inheritence.

This fixes llvm.org/PR15179.

Before:
class ColorChooserMac : public content::ColorChooser,
    public content::WebContentsObserver {
};

After:
class ColorChooserMac : public content::ColorChooser,
                        public content::WebContentsObserver {
};

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175147 91177308-0d34-0410-b5e6-96231b3b80d8