Implement ANGLE_copy_texture_3d Extension

Adds copyTexture3DANGLE and copySubTexture3DANGLE that adds copy
operations on volumetric textures.

Bug: angleproject:2762
Test: angle_end2end_tests

Change-Id: I0076989c2b7ed69abfc73143c325065bdb06a360
Reviewed-on: https://chromium-review.googlesource.com/c/1207216
Commit-Queue: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Jamie Madill <jmadill@chromium.org>
diff --git a/src/libANGLE/renderer/renderer_utils.h b/src/libANGLE/renderer/renderer_utils.h
index 64a258e..cf1ff8d 100644
--- a/src/libANGLE/renderer/renderer_utils.h
+++ b/src/libANGLE/renderer/renderer_utils.h
@@ -208,15 +208,18 @@
 void CopyImageCHROMIUM(const uint8_t *sourceData,
                        size_t sourceRowPitch,
                        size_t sourcePixelBytes,
+                       size_t sourceDepthPitch,
                        PixelReadFunction pixelReadFunction,
                        uint8_t *destData,
                        size_t destRowPitch,
                        size_t destPixelBytes,
+                       size_t destDepthPitch,
                        PixelWriteFunction pixelWriteFunction,
                        GLenum destUnsizedFormat,
                        GLenum destComponentType,
                        size_t width,
                        size_t height,
+                       size_t depth,
                        bool unpackFlipY,
                        bool unpackPremultiplyAlpha,
                        bool unpackUnmultiplyAlpha);