Clean up webgl Swangle/Mac suppressions

These two tests pass.

Bug: chromium:1099979
Change-Id: I76b553918990e3a4d768c93888a9990391237dee
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2363808Reviewed-by: Yuly Novikov <ynovikov@chromium.org>
Commit-Queue: Jonah Ryan-Davis <jonahr@google.com>
Cr-Commit-Position: refs/heads/master@{#800141}

content/test/gpu/gpu_tests/test_expectations/webgl_conformance_expectations.txt

@@ -793,7 +793,6 @@ crbug.com/1099978 [ mac swiftshader passthrough ] conformance/glsl/samplers/glsl
 crbug.com/1102991 [ mac swiftshader passthrough ] conformance/more/functions/copyTexSubImage2D.html [ RetryOnFailure ]
 crbug.com/1102991 [ mac swiftshader passthrough ] conformance/more/functions/deleteBufferBadArgs.html [ RetryOnFailure ]
 crbug.com/1102991 [ mac swiftshader passthrough ] conformance/more/glsl/uniformOutOfBounds.html [ RetryOnFailure ]
-crbug.com/1099979 [ mac swiftshader passthrough ] conformance/misc/uninitialized-test.html [ Failure ]
 crbug.com/1099978 [ mac swiftshader passthrough ] conformance/reading/read-pixels-test.html [ Failure ]
 crbug.com/1099978 [ mac swiftshader passthrough ] conformance/renderbuffers/renderbuffer-initialization.html [ Failure ]
 crbug.com/1099979 [ mac swiftshader passthrough ] conformance/rendering/draw-webgl-to-canvas-2d-repeatedly.html [ Failure ]
@@ -818,7 +817,6 @@ crbug.com/1099979 [ mac swiftshader passthrough ] conformance/textures/image_bit
 crbug.com/1099979 [ mac swiftshader passthrough ] conformance/textures/image_bitmap_from_video/tex-2d-rgba-rgba-unsigned_byte.html [ Failure ]
 crbug.com/1099979 [ mac swiftshader passthrough ] conformance/textures/image_bitmap_from_video/tex-2d-rgba-rgba-unsigned_short_4_4_4_4.html [ Failure ]
 crbug.com/1099979 [ mac swiftshader passthrough ] conformance/textures/image_bitmap_from_video/tex-2d-rgba-rgba-unsigned_short_5_5_5_1.html [ Failure ]
-crbug.com/1099979 [ mac swiftshader passthrough ] conformance/textures/misc/copy-tex-image-2d-formats.html [ Failure ]
 crbug.com/1099979 [ mac swiftshader passthrough ] conformance/textures/misc/gl-pixelstorei.html [ Failure ]
 crbug.com/1102991 [ mac swiftshader passthrough ] conformance/textures/misc/tex-image-and-sub-image-2d-with-array-buffer-view.html [ RetryOnFailure ]
 crbug.com/1099979 [ mac swiftshader passthrough ] conformance/textures/misc/texparameter-test.html [ Failure ]