clang-format: [ObjC] Wrap ObjC method declarations before annotations.

Before:
  - (instancetype)initXxxxxxxxxxxxxxxxxxxxxxxxx:(id<x>)x
                                              y:(id<yyyyyyyyyyyyyyyyyyyy>)
                                                    y NS_DESIGNATED_INITIALIZER;
After:
  - (instancetype)initXxxxxxxxxxxxxxxxxxxxxxxxx:(id<x>)x
                                              y:(id<yyyyyyyyyyyyyyyyyyyy>)y
      NS_DESIGNATED_INITIALIZER;

llvm-svn: 219564