Use testharness.js instead of js-test.js in LayoutTests/fast/canvas tests.

third_party/WebKit/LayoutTests/fast/canvas/script-tests/canvas-getImageData-negative-source.js

-description("Test the handling of negative sourceRect offset in getImageData().");
-
-ctx = document.createElement('canvas').getContext('2d');
-
-ctx.fillStyle = 'red';
-ctx.fillRect(0, 0, 100, 100);
-ctx.fillStyle = 'green';
-ctx.fillRect(0, 0, 6, 6);
-
-var imageData = ctx.getImageData(-10, 0, 100, 1);
-var imgdata = imageData.data;
-
-// Fully transparent black
-shouldBe("imgdata[0]", "0");
-shouldBe("imgdata[1]", "0");
-shouldBe("imgdata[2]", "0");
-shouldBe("imgdata[3]", "0");
-
-// Green
-shouldBe("imgdata[60]", "0");
-shouldBe("imgdata[61]", "128");
-shouldBe("imgdata[62]", "0");
-shouldBe("imgdata[63]", "255");
-
-// Red
-shouldBe("imgdata[64]", "255");
-shouldBe("imgdata[65]", "0");
-shouldBe("imgdata[66]", "0");
-shouldBe("imgdata[67]", "255");