ShaderCache: Implement background shader compilation

This enables shaders to be compiled while the game is starting, instead
of blocking startup. If a shader is needed before it is compiled,
emulation will block.

Source/Core/VideoCommon/VideoCommon.vcxproj

@@ -120,6 +120,7 @@
     <ClInclude Include="Fifo.h" />
     <ClInclude Include="FPSCounter.h" />
     <ClInclude Include="FramebufferManagerBase.h" />
+    <ClInclude Include="GXPipelineTypes.h" />
     <ClInclude Include="ShaderCache.h" />
     <ClInclude Include="UberShaderCommon.h" />
     <ClInclude Include="UberShaderPixel.h" />
@@ -190,4 +191,4 @@
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
   <ImportGroup Label="ExtensionTargets">
   </ImportGroup>
-</Project>
+</Project>