Bug 1382718 - Expose ImageUtils.h so utils can be used more widely. r=mattwoodrow

MozReview-Commit-ID: D5AyqzCCXaj

--HG--
extra : rebase_source : 2e7b2c339ee6b8242c50816ed248d0b0dbf4b8fb

dom/canvas/moz.build

@@ -66,6 +66,7 @@ EXPORTS.mozilla.dom += [
     'ImageBitmapRenderingContext.h',
     'ImageBitmapSource.h',
     'ImageData.h',
+    'ImageUtils.h',
     'OffscreenCanvas.h',
     'TextMetrics.h',
     'WebGLVertexArrayObject.h',