The code in VkPipelineCache was correctly comparing all the attributes
of the specialization constants and then was also doing a faulty shared
pointer comparison. This was causing major drag on draw calls as every
draw call in ANGLE was recompiling the shader.

Bug: angleproject:4426
Change-Id: Ia0466738eb7de78c0c3b53e61e2f2bc6831bbcca
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/41688
Kokoro-Presubmit: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Nicolas Capens <nicolascapens@google.com>
Tested-by: Nicolas Capens <nicolascapens@google.com>