Refactor GLProfiler

[dany-on-demand]

Right, now, OS is creating a new GLProfiler object each step of the frame. Even if debugging is turned off.

[yvt]

Creation cost of GLProfile automatic variable every frame shouldn't be high because:

• Because GLProfile is always allocated with automatic variable, memory allocation for GLProfile is done by shifting stack pointer register, not by dynamic allocation.
• Only a few dozens of GLProfile is created every frame. Calling constructors 100 times per frame shouldn't costly.

[Ericson2314]

FYI automatic variable != stack variable in C++ due to RAII. But if GLProfile's constructor does indeed allocate on the stack yeah, shouldn't be a problem @dany0.

[dany-on-demand]

Guess you can close the issue then.