…some Blinn-Phong texture animations. (#2971)

* Partial solution to #2744 crash with better error handling.

Handles shader compile errors better, and should turn crash into an LL_ERRS assertion failure.
Strengthed more assertions and improved shader error line numbers

* Even more error handling to get a handle on crash #2744
* Improved GLSL correctness on Intel chips that lack OpenGL 4.6 support. #2744
* Removed non-working fallback code for gDeferredPostProgram
* Fixed incorrect llmax call

Looks like floater expired while waiting for response

…oading. Miscellaneous cleanup and comments.

Seems to be realted to LLModelPreview and path generated textures so I'm
improving cleanup.

destroyRawImage is the only function that calls saveRawImage(), not
calling it results in fetcher thinking that it still needs data to do
the saving and looping back to trying to fetch.

#3104: Fix outfit gallery pictures sometimes not loading. Remove texture resolution restriction.

…trigger for intel HD 4X00 gpus

… machines

i.e. hardware that has a hard time running visual studio and tracy.

for example, use it by running `autobuild configure -- -DLOCAL_DIST_DIR=dist/secondlife`
and then export that directory under your build tree as a shared folder.

#2744 intel fallback cleanups

#2768, #2848: Partial cherry pick of "Animated pbr textures don't animate" from develop

* #3103 Add the ability to disable the emissive buffer for older GPUs with low memory bandwidth.
* #3135 Add a "vintage" mode for slower GPUs
* #2719 Fix for skies being overbrightened
* #2632 Do not apply tonemapping on legacy skies

Co-authored-by: Alexander Gavriliuk <alexandrgproductengine@lindenlab.com>

when both thumnail and normal image attempt to fetch, one creates a
fetcher, another fails, since fetcher is already there, potentially in a
transitional state, so it thinks fetch failed.

* #3157 Fix alpha not having ambient lighting on low.

Apparently made a blunder in previous commit since I missed mFetchState
being reset each run

…lity modes.

Also make extra sure vintage mode is enabled when GL3 is detected.

Add diagnostic output for LLProcess event history failure.

…evelop

 # Conflicts:
 #	indra/newview/featuretable.txt
 #	indra/newview/llfeaturemanager.cpp
 #	indra/newview/llviewerdisplay.cpp
 #	indra/newview/llviewershadermgr.cpp
 #	indra/newview/llvovolume.cpp
 #	indra/newview/pipeline.cpp

ExtraFPS -> develop merge

# Conflicts:
#	indra/newview/llmaterialeditor.cpp