--HG--
branch : RLVa

including safety checks and some refactoring

including safety checks and some refactoring

including safety checks and some refactoring

Introduce helper classes to manage paired initProfile() / finishProfile()
calls and gBenchmarkProgram.bind() / unbind() calls.

Make TextureHolder a class instead of a struct.

Per Henri Beauchamp, since gpu_benchmark() takes a very early exit if
(!gGLManager.mHasTimerQuery), subsequent tests of mHasTimerQuery are
redundant. Remove.

One of those tests controls the busted_finish bool, which can never become
true. Remove that and all tests on it.

A classic-C array doesn't destroy its individual elements, but a std::vector
does. Use a std::vector<LLRenderTarget> for dest, so each LLRenderTarget will
be destroyed. ~LLRenderTarget() calls its release() method.

Ruslan tracked the observed crash to assignments (to create a dummy triangle)
through an LLStrider<LLVector3> obtained from getVertexStrider(). When
getVertexStrider() returns false, produce a warning and just skip the rest of
the benchmark test.

The one bit of explicit cleanup apparently required by that early exit is a
call to LLImageGL::deleteTextures() to match the preceding generateTextures()
call. Wrap both in a new TextureHolder class whose destructor takes care of
cleanup. The only other references to the corresponding U32 array are a couple
calls to LLTexUnit::bindManual(); add a bind() method to support that.

Also fix apparent bug in the LL_DARWIN special case for "improbably high and
likely incorrect": the code assigned -1.f (the "couldn't compute" value) to
gbps, overlooking the fact that gbps is unconditionally recomputed below. In
the "likely incorrect" stanza, simply return -1.f instead.

In case of buff->getVertexStrider(v) return false it mean that glMapBufferRange() return NULL
The next three lines can be the reason of this crash.

--HG--
branch : RLVa

--HG--
branch : RLVa

Rename llround(..) to ll_round(..) because of a collision with MS llround (long long round) in VS2013

Avoid using GL_ARB_timer_query functionality when not supported and protect against probably-not-NULL current bound shader pointer