Clean up copyvertex.h

 * Move "private" functions into copyvertex.inl.
 * Capitalize global function names give them more descriptive names.
 * Use size_t for all dimensions.
 * Use uint8_t pointers instead of unsigned char pointers.

Change-Id: I408cf7ebb28655c5811ad18979a20f4273d278cd
Reviewed-on: https://chromium-review.googlesource.com/207373
Reviewed-by: Brandon Jones <bajones@chromium.org>
Tested-by: Geoff Lang <geofflang@chromium.org>
diff --git a/src/libGLESv2/formatutils.h b/src/libGLESv2/formatutils.h
index 1fc1c1f..112fc6d 100644
--- a/src/libGLESv2/formatutils.h
+++ b/src/libGLESv2/formatutils.h
@@ -31,7 +31,7 @@
 typedef void (*ColorWriteFunction)(const void *source, void *dest);
 typedef void (*ColorCopyFunction)(const void *source, void *dest);
 
-typedef void (*VertexCopyFunction)(const void *input, size_t stride, size_t count, void *output);
+typedef void (*VertexCopyFunction)(const uint8_t *input, size_t stride, size_t count, uint8_t *output);
 
 namespace gl
 {