Placeholder object for VkPipelineCache

While implementing Pipeline Cache is optional, we still need a
placeholder object in order to return have a valid handle for
this object.

b/118386749

Change-Id: I18abb4196fbc99d3f639c1ba14ceb570ac11b365
Reviewed-on: https://swiftshader-review.googlesource.com/c/22729
Reviewed-by: Nicolas Capens <nicolascapens@google.com>
Tested-by: Alexis Hétu <sugoi@google.com>
diff --git a/src/Vulkan/VkPipelineCache.hpp b/src/Vulkan/VkPipelineCache.hpp
new file mode 100644
index 0000000..6218394
--- /dev/null
+++ b/src/Vulkan/VkPipelineCache.hpp
@@ -0,0 +1,47 @@
+// Copyright 2018 The SwiftShader Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef VK_PIPELINE_CACHE_HPP_
+#define VK_PIPELINE_CACHE_HPP_
+
+#include "VkObject.hpp"
+
+namespace vk
+{
+
+class PipelineCache : public Object<PipelineCache, VkPipelineCache>
+{
+public:
+	PipelineCache(const VkPipelineCacheCreateInfo* pCreateInfo, void* mem)
+	{
+	}
+
+	~PipelineCache() = delete;
+
+	static size_t ComputeRequiredAllocationSize(const VkPipelineCacheCreateInfo* pCreateInfo)
+	{
+		return 0;
+	}
+
+private:
+};
+
+static inline PipelineCache* Cast(VkPipelineCache object)
+{
+	return reinterpret_cast<PipelineCache*>(object);
+}
+
+} // namespace vk
+
+#endif // VK_PIPELINE_CACHE_HPP_