Add VulkanContextProvider to RasterDecoderContextState.

Add VulkanContextProvider to RasterDecoderContextState which is needed
to get VkDevice in shareable image. Refactor RasterDecoderContextState
class to have seperate constructors for Vulkan and GL.

Bug: 891060
Change-Id: I0ca7e657d33fdcfa62ab6465f7023a914610b7ce
Reviewed-on: https://chromium-review.googlesource.com/c/1312194
Commit-Queue: vikas soni <vikassoni@chromium.org>
Reviewed-by: Eric Karl <ericrk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#605146}
7 files changed