Fix the most obvious issues in J3DIMath and add basic tests

Interface description was edited to match what the code does, cross
product now produces the correct results, and basic unit tests for
the functions where problems were found were added.

Note that WebKitCSSMatrix behavior does not seem to match docs in current
browsers: m12 represents the value in the 2nd row, not in 2nd column like
the class reference says [1]. The actual behavior is similar to how
J3DIMath implements it in JavaScript.

[1] See https://developer.apple.com/library/safari/documentation/AudioVideo/Reference/WebKitCSSMatrixClassReference
 Add a case for getTexParameter() returning correct float values.

Also, fix a bug in shaders-with-mis-matching-uniforms.html (fragment shader missing float precision)
Merge pull request #490 from zhenyao/fix

 Add a case for getTexParameter() returning correct float values.
Assign new test's copyright to Khronos

The header is copied from webgl-conformance-tests.html
Disallow compressedTexSubImage2D for ETC1 format

The original spec doesn't allow it, so we probably shouldn't either.
Merge pull request #491 from jdashg/etc1-no-sub

Disallow compressedTexSubImage2D for ETC1 format
Merge pull request #489 from NVIDIA/j3dimath-improvement

Fix the most obvious issues in J3DIMath and add basic tests
Fixed inverted test of WebGLContextEvent's "canceled" flag. Thanks to Justin Novosad for pointing out the bug. Updated modified and copyright dates.
Merge pull request #493 from kenrussell/cancelable-flag

Fixed inverted test of WebGLContextEvent's "canceled" flag. Thanks to Ju...
Make WEBGL_depth_texture refer to right section in main spec
ANGLE_instanced_arrays extension addendum for index validation

This makes the specification to have reasonable security and stability
guarantees and match what at least Chrome has already implemented.
Merge pull request #494 from NVIDIA/fix-extension-refs

Make WEBGL_depth_texture refer to right section in main spec
Merge pull request #495 from NVIDIA/fix-angle-instanced-arrays-spec

ANGLE_instanced_arrays extension addendum for index validation
Add proposal for WEBGL_draw_elements_no_range_check

The goal of the extension is to eliminate one common source of WebGL CPU
overhead by removing drawElements index validation.

The extension changes the behavior of drawElements as opposed to
introducing a new call or a toggleable flag to make it possible to get
rid of index buffer copies in CPU memory entirely after the extension
has been enabled.
Added check for a potential texture binding regressionin Chrome
Typo. it's -> its
Merge pull request #496 from toji/binding_loss

Added check for a potential texture binding regression in Chrome
Remove precision qualifiers from booleans in constructor tests

Use default precision qualifiers for float and int instead. Booleans or
literals do not have precision qualifiers.
Add tests for a literal and booleans with a precision qualifier

According to GLSL spec, boolean variables and literals do not
have a precision qualifier, so compilation should fail in these cases.
Add simple benchmark for drawElements index validation overhead

The test changes data in an index buffer and calls drawElements on it.
There are always some invalid indices in the buffer, so that any drawing
is not performed but the test just measures the overhead from uploading
data and performing validation.

The test is written to specifically target implementations in Chrome and
Firefox in March 2014, so some of the results might be slightly
misleading on other implementations.