For loops with variable declaration messes up token input/output positions

[mstorsjo]

This input gets converted incorrectly
int main () { for( int i = 0; i < 9; i++ ); return 0; }
into this:
int main () { { int i = 0; for( ; i < 9; i++ ); }return0; }

The token input/output positions need to be updated correctly.. somewhere.., so we produce enough whitespace between "return0;". I added a test case for it in a branch in my repo as well: mstorsjo@for-loop-test

This exact piece of code is used in x264's configure script for testing for the C99 features.