Expand the sample_texture_combo test to include storage textures.

[greggman]

The spec specifies there is a maximum number of texture + sampler combinations and a maximum number of storage textures in vertex and fragment stages.

Test that you can use all of them at the same time to the maximum limit of the adapter.

[shrekshao]

I ran this on linux google-chrome-unstable opengles compat and got this error log (exp color changed 32769 (0x0180) -> 32778 (0x0A80)):

webgpu:api,operation,sampling,sampler_texture:sample_texture_combos:
246.0000 ms

EXPECTATION FAILED: Texture level had unexpected contents:
 between 1,1,0 and 15,1,0 inclusive:
                            coords == X,Y,Z:       1,1,0       2,1,0       3,1,0       4,1,0       5,1,0       6,1,0       7,1,0 ...
  act. texel bytes (little-endian) ==    0x: 01 00 02 00 01 00 03 00 01 00 04 00 01 00 05 00 01 00 06 00 01 00 07 00 01 00 08 00 ...
                       act. colors ==   R,G:         1,2         1,3         1,4         1,5         1,6         1,7         1,8 ...
                       exp. colors ==   R,G:     32778,2     32778,3     32778,4     32778,5     32778,6     32778,7     32778,8 ...
        act. normal-ULPs-from-zero ==   R,G:         1,2         1,3         1,4         1,5         1,6         1,7         1,8 ...
        exp. normal-ULPs-from-zero ==   R,G:     32778,2     32778,3     32778,4     32778,5     32778,6     32778,7     32778,8 ...
                     tolerance ± 0
                  diff (act - exp) ==           -32777,0    -32777,0    -32777,0    -32777,0    -32777,0    -32777,0    -32777,0 ...
Error
    at TextureExpectations.eventualAsyncExpectation (http://localhost:8080/out/common/framework/fixture.js:254:24)
    at TextureExpectations.eventualExpectOK (http://localhost:8080/out/common/framework/fixture.js:396:10)
    at TextureExpectations.expectTexelViewComparisonIsOkInTexture (http://localhost:8080/out/webgpu/gpu_test.js:1945:12)
    at RunCaseSpecific.fn (http://localhost:8080/out/webgpu/api/operation/sampling/sampler_texture.spec.js:336:5)

[greggman]

Yes, the GL backend doesn't pass. That's the point

It also doesn't pass before this change.

[shrekshao]

Oh but fails on linux core as well, is this expected?

webgpu:api,operation,sampling,sampler_texture:sample_texture_combos:
381.4000 ms

EXPECTATION FAILED: Texture level had unexpected contents:
 between 256,0,0 and 263,1,0 inclusive:
                            coords == X,Y,Z:     256,0,0     257,0,0     258,0,0     259,0,0     260,0,0     261,0,0     262,0,0 ...
  act. texel bytes (little-endian) ==    0x: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ...
                       act. colors ==   R,G:         0,0         0,0         0,0         0,0         0,0         0,0         0,0 ...
                       exp. colors ==   R,G:        17,0        18,0        19,0        20,0        21,0        22,0        23,0 ...
        act. normal-ULPs-from-zero ==   R,G:         0,0         0,0         0,0         0,0         0,0         0,0         0,0 ...
        exp. normal-ULPs-from-zero ==   R,G:        17,0        18,0        19,0        20,0        21,0        22,0        23,0 ...
                     tolerance ± 0
                  diff (act - exp) ==              -17,0       -18,0       -19,0       -20,0       -21,0       -22,0       -23,0 ...
Error
    at TextureExpectations.eventualAsyncExpectation (http://localhost:8080/out/common/framework/fixture.js:254:24)
    at TextureExpectations.eventualExpectOK (http://localhost:8080/out/common/framework/fixture.js:396:10)
    at TextureExpectations.expectTexelViewComparisonIsOkInTexture (http://localhost:8080/out/webgpu/gpu_test.js:1945:12)
    at RunCaseSpecific.fn (http://localhost:8080/out/webgpu/api/operation/sampling/sampler_texture.spec.js:336:5)

[greggman]

Fixed for Vulkan. It was calling textureLoad out of bounds and that behavior is implementation defined. It no longer does that. Still fails on GL.