An extra line of error recovery code set a non-sense combination of
es version and core profile.

'invocations' was using 0 as the "shader never set" flag and as the
default. Formalize this and explicit set to 1 and link time.

To do this, more generally use a named -1 as a not set value.

SPV: Smear should use type of the scalar to make the expected vector type when the provided vector type is incompatible with the scalar.

Parser: Extension requirement of gl_PrimitiveID and gl_Layer should be checked only for ESSL instead of GLSL.

expected vector type when the provided vector type is incompatible with
the scalar.

Parser: Extension requirement of gl_PrimitiveID and gl_Layer should be checked only for ESSL instead of GLSL.

SPV: Implement GLSL interpolation built-in functions.

Dealing with the 110 toolset seems not worth it.

Avoid read past end of operands vector for EOpFrexp

When emitting SPIR-V code for frexp, avoid access
beyond the end of the operands vector.  When constructing
the OpExtInst, construct a new arguments vector instead of
modifying the existing operands vector.  In the case of OpFrexp,
well need that last operand later on to generate the store.

Fixes https://github.com/KhronosGroup/glslang/issues/110

Change-Id: Ibc380fadf5e600ac491932e9ecef7afe2d72fd7f

SPV: Distinguish between std140 and std430 layouts, and correctly use alignments as the base for strides.

Scanner optimisations

In addUnaryMath, check for 'child' being null before dereferencing it.

Fail InitProcess() when InitThread() fails.

Fix ordered pointer comparison build warning/error

Use generic osinclude.h.

Using platform-neutral osinclude.h makes it easier to substitute
implementation when necessary and eliminates some variability between
build configurations.

Also, generally allow ES variable indexing of in/out blocks.

Handles the case of
    float[] x = float[] (1.0, 2.0, 3.0),
            y = float[] (1.0, 2.0, 3.0, 4.0);
where a shallow copy of the type arrayness from the left-most float[]
was getting used twice.

SPV: Fix an issue related with using CubeArrayShadow for texture()

Build: Use common osinclude.h header file that redirects per-platform, remove obsolete build files, enforce relative includes.