Merge remote-tracking branch 'aosp/upstream-master'
Pulls in the following:
27d98e2 Merge pull request #181 from antiagainst/readme
29ca6f9 Use footnotes for links in README.md.
4897864 Grammar update: OpPhi now uses PairIdRefIdRef as the last operand.
11636fb Update the core grammar.
469f0e8 Make paths to grammar output files
8ba7c92 Remove revision from SPV_ENV_*.
670c0ac Allow to only build certain grammar tables.
051e067 Remove the outdated patch file.
7649c73 Fix MSVC error C2797.
80e416c Use JSON grammar files to generate extended instruction sets.
9ca2d6d Rname grammar.json to spirv.core.grammar.json and add version info.
3fb2676 Fix validation of array length.
6fa3f8a Remove dependency on SPIR-V headers in libspirv.h.
d03c0a1 Enable linking against libSPIRV-Tools from linux shared libraries
c9b2285 Fix spelling mistakes
4f293b7 Use the JSON grammar file to generate various info tables.
a1de2b3 Handle CRLF in assembly text.
3d27da4 Add a target environment to spvContextCreate().
6836e17 OpExecutionMode only takes a single ExecutionMode
4529146 Capability fix: ImageReadWrite & ImageMipmap require ImageBasic.
