Remove duplicated WebGL layout tests.

third_party/WebKit/LayoutTests/fast/canvas/webgl/tex-image-and-sub-image-2d-with-canvas-rgb565-expected.txt

-Verify texImage2D and texSubImage2D code paths taking canvas elements (RGB/UNSIGNED_SHORT_5_6_5)
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-On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE".
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-PASS successfullyParsed is true
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-TEST COMPLETE
-Testing texImage2D with flipY=true
-Checking lower left corner
-PASS shouldBe 0,255,0
-Checking upper left corner
-PASS shouldBe 255,0,0
-Checking if pixel values in source canvas change after canvas used as webgl texture
-PASS Pixel values in source canvas remain unchanged after canvas used in webgl texture.
-Testing texImage2D with flipY=false
-Checking lower left corner
-PASS shouldBe 255,0,0
-Checking upper left corner
-PASS shouldBe 0,255,0
-Checking if pixel values in source canvas change after canvas used as webgl texture
-PASS Pixel values in source canvas remain unchanged after canvas used in webgl texture.
-Testing texSubImage2D with flipY=true
-Checking lower left corner
-PASS shouldBe 0,255,0
-Checking upper left corner
-PASS shouldBe 255,0,0
-Checking if pixel values in source canvas change after canvas used as webgl texture
-PASS Pixel values in source canvas remain unchanged after canvas used in webgl texture.
-Testing texSubImage2D with flipY=false
-Checking lower left corner
-PASS shouldBe 255,0,0
-Checking upper left corner
-PASS shouldBe 0,255,0
-Checking if pixel values in source canvas change after canvas used as webgl texture
-PASS Pixel values in source canvas remain unchanged after canvas used in webgl texture.
-PASS getError was expected value: NO_ERROR : should be no errors
-PASS successfullyParsed is true
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-TEST COMPLETE
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