Get GeneralHrdParams from VPS or SPS depending on where it is present

Roman Guskov authored 2 years ago and Nikolay Shostak committed 2 years ago

Call pop_front() to prevent infinite loop

Avoid having a separate PTL count since we already have a size
for the vector containing the PTLs.

Add a size check to avoid writing into inexistant PTL. This may
avoid bug reports such as #1587

This reverts commit 21980b28fb5e9fb78ff6b1dda90118c23271e650.

- reset passed string argument
- remove unnecessary pointers
- don't add zero termination character to C++ string

Macro: JVET_AB0070_POST_FILTER_HINT