[clang-format] Process line's children once in guessIsObjC

lib/Format/Format.cpp

for (auto Line : AnnotatedLines) {
                                 FormatTok->TokenText)) ||
             FormatTok->is(TT_ObjCStringLiteral) ||
             FormatTok->isOneOf(Keywords.kw_NS_ENUM, Keywords.kw_NS_OPTIONS,
                                TT_ObjCBlockLBrace, TT_ObjCBlockLParen,
                                TT_ObjCDecl, TT_ObjCForIn, TT_ObjCMethodExpr,
                                TT_ObjCMethodSpecifier, TT_ObjCProperty)) {
           return true;
         }
-        if (guessIsObjC(Line->Children, Keywords))
-          return true;
-      }
-    }
+      }
     return false;
   }
 
   bool IsObjC;
 };
 
 struct IncludeDirective {
   StringRef Filename;