VideoBackends / VideoCommon: add support for specifying include files in shader code

Source/Core/VideoBackends/OGL/OGLGfx.h

@@ -25,8 +25,10 @@ public:
                                                  std::string_view name) override;
   std::unique_ptr<AbstractStagingTexture>
   CreateStagingTexture(StagingTextureType type, const TextureConfig& config) override;
-  std::unique_ptr<AbstractShader> CreateShaderFromSource(ShaderStage stage, std::string_view source,
-                                                         std::string_view name) override;
+  std::unique_ptr<AbstractShader>
+  CreateShaderFromSource(ShaderStage stage, std::string_view source,
+                         VideoCommon::ShaderIncluder* shader_includer,
+                         std::string_view name) override;
   std::unique_ptr<AbstractShader> CreateShaderFromBinary(ShaderStage stage, const void* data,
                                                          size_t length,
                                                          std::string_view name) override;