UserAgent: Mozilla/5.0 (Windows NT 6.3; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/51.0.2704.103 Safari/537.36

Steps to reproduce the problem:
On macOS machines with certain Intel GPUs, if we create a texture and upload data per level in a random sequence, the result is not correct if we read every level's data in sequence. For example, we create a texture with width=32, height = 4 and r16ui format. Use the level sequence (0, 1, 5, 3, 4, 2) to upload the corresponding level's data. And then use this texture as the fragment shader's output color in a sequential level order. Based on the data we got, the actual order is like (1, 2, 3, 3, 4, 5). But the expected order should be (0, 1, 2, 3, 4, 5). This bug causes failures of random_teximage2d_2d.html's tests in the WebGL 2.0 conformance suite.

This bug does not occur on other GPU types on macOS, nor on other operating systems.

Steps to reproduce

1. Download Chrome Canary and run from the Terminal:
/Applications/Google\ Chrome\ Canary.app/Contents/MacOS/Google\ Chrome\ Canary --enable-unsafe-es3-apis

2. Check out the KhronosGroup/WebGL repository:
git clone https://github.com/KhronosGroup/WebGL.git

3. Launch an HTTP server against that repository:
cd WebGL
python -m SimpleHTTPServer

4. Navigate the browser to the test cases:
http://localhost:8000/sdk/tests/deqp/functional/gles3/texturespecification/random_teximage2d_2d.html?webglVersion=2&quiet=0?webglVersion=2&quiet=0
This test is also available online at:
https://www.khronos.org/registry/webgl/sdk/tests/deqp/functional/gles3/texturespecification/random_teximage2d_2d.html?webglVersion=2&quiet=0

What is the expected behavior?
Expect all tests to pass, as they do on other operating systems and on other GPU types on macOS.

What went wrong?
test case: specification.random_teximage2d.2d.r16ui fails.

Did this work before? N/A 

Does this work in other browsers? N/A

Chrome version: 55.0.2868.0  Channel: n/a
OS Version: 10.12
Flash Version: 

OS X Build/Version
macOS Sierra version 10.12
BAD MacBook Pro-Mid 2015-Intel Iris Pro Graphics 5200
GOOD MacBook-Early2016-Intel HD Graphics 515