Remove the dependency on mProgramState/mProgramPipelineState for the
following functions in ProgramExecutable:

hasUniformBuffers()
hasStorageBuffers()
hasAtomicCounterBuffers()
hasTransformFeedbackOutput()
getTransformFeedbackBufferCount()

The data structures those function were querying were recently moved
into the ProgramExecutable, so the call stack was:
ProgramExecutable -> ProgramState -> ProgramExecutable

This change updates the functions to return the results immediately.

Remaining functions to be cleaned up in later CLs:

hasDefaultUniforms()
hasTextures()
hasImages()

Bug: angleproject:4520
Test: Build/CQ
Change-Id: Ieaa041ff128e389f322745d55f688d4b07a5a23d
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2216764Reviewed-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org>
Commit-Queue: Tim Van Patten <timvp@google.com>