The ObjC-block detection code only supports a single token as the return type. Add support to detect pointers, too (ObjC has lots of object-pointers).
For example, using `BasedOnStyle: WebKit`, the following is stable output:
```
int* p = ^int*(void)
{ //
return nullptr;
}
();
```
After the patch, this is stable:
```
int* p = ^int*(void) { //
return nullptr;
}();
```
Differential Review: https://reviews.llvm.org/D146434
63d6659a04