ANGLE: Array Bounds Clamper for WebKit

Implements clamping of array indexing expressions during shader translation.

Used on Windows to implement OpenGL ES on top of DirectX. Configure with -no-opengl, or -opengl desktop to exclude.

The sources can be found in qtbase-opensource-src-o6Kp20/qtbase-opensource-src-5.15.8+dfsg/src/3rdparty/angle/src/third_party/compiler.

 Copyright (C) 2012 Apple Inc.

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