Added Mock GoogleTest folder for PolicyLibCommon (microsoft#780)

Issue microsoft#867

cherry-pick from c8f9883

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Added Mock GoogleTest folder for PolicyLibCommon

For each item, place an "x" in between `[` and `]` if true. Example:
`[x]`.
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- [ ] Impacts functionality?
- **Functionality** - Does the change ultimately impact how firmware
functions?
- Examples: Add a new library, publish a new PPI, update an algorithm,
...
- [ ] Impacts security?
- **Security** - Does the change have a direct security impact on an
application,
    flow, or firmware?
  - Examples: Crypto algorithm change, buffer overflow fix, parameter
    validation improvement, ...
- [ ] Breaking change?
- **Breaking change** - Will anyone consuming this change experience a
break
    in build or boot behavior?
- Examples: Add a new library class, move a module to a different repo,
call
    a function in a new library class in a pre-existing module, ...
- [ ] Includes tests?
  - **Tests** - Does the change include any explicit test code?
  - Examples: Unit tests, integration tests, robot tests, ...
- [ ] Includes documentation?
- **Documentation** - Does the change contain explicit documentation
additions
    outside direct code modifications (and comments)?
- Examples: Update readme file, add feature readme file, link to
documentation
    on an a separate Web page, ...

Added this mock lib definition and declaration to one of the library
under Gen 11 and made sure local build is successful

N/A

PolicyServicePkg/PolicyServicePkg.dec

@@ -14,6 +14,7 @@
 
 [Includes]
   Include
+  Test/Mock/Include
 
 [LibraryClasses]
   PolicyLib|Include/Library/PolicyLib.h

PolicyServicePkg/Test/Mock/Include/GoogleTest/Library/MockPolicyLibCommon.h

@@ -0,0 +1,33 @@
+/** @file
+  Google Test mocks for PolicyLibCommon
+
+  Copyright (c) Microsoft Corporation.
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+**/
+
+#ifndef MOCK_POLICY_LIB_COMMON_LIB_H_
+#define MOCK_POLICY_LIB_COMMON_LIB_H_
+
+#include <Library/GoogleTestLib.h>
+#include <Library/FunctionMockLib.h>
+extern "C" {
+  #include <Uefi.h>
+  #include <Library/PolicyLib.h>
+}
+
+struct MockPolicyLibCommon {
+  MOCK_INTERFACE_DECLARATION (MockPolicyLibCommon);
+
+  MOCK_FUNCTION_DECLARATION (
+    EFI_STATUS,
+    GetPolicy,
+    (
+     IN CONST EFI_GUID  *PolicyGuid,
+     OUT UINT64         *Attributes OPTIONAL,
+     OUT VOID           *Policy,
+     IN OUT UINT16      *PolicySize
+    )
+    );
+};
+
+#endif

PolicyServicePkg/Test/Mock/Library/GoogleTest/MockPolicyLibCommon/MockPolicyLibCommon.cpp

@@ -0,0 +1,11 @@
+/** @file
+  Google Test mocks for PolicyLibCommon
+
+  Copyright (c) Microsoft Corporation.
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+**/
+
+#include <GoogleTest/Library/MockPolicyLibCommon.h>
+
+MOCK_INTERFACE_DEFINITION (MockPolicyLibCommon);
+MOCK_FUNCTION_DEFINITION (MockPolicyLibCommon, GetPolicy, 4, EFIAPI);

PolicyServicePkg/Test/Mock/Library/GoogleTest/MockPolicyLibCommon/MockPolicyLibCommon.inf

@@ -0,0 +1,33 @@
+## @file
+# Google Test mocks for PolicyLibCommon
+#
+# Copyright (c) Microsoft Corporation.
+# SPDX-License-Identifier: BSD-2-Clause-Patent
+##
+
+[Defines]
+  INF_VERSION                    = 0x00010005
+  BASE_NAME                      = MockPolicyLibCommon
+  FILE_GUID                      = 65E475F7-FD55-4008-A0E7-F63495C3C5DC
+  MODULE_TYPE                    = HOST_APPLICATION
+  VERSION_STRING                 = 1.0
+  LIBRARY_CLASS                  = PolicyLib
+  PI_SPECIFICATION_VERSION       = 0x0001000A
+
+#
+#  VALID_ARCHITECTURES           = IA32 X64
+#
+
+[Sources]
+  MockPolicyLibCommon.cpp
+
+[Packages]
+  MdePkg/MdePkg.dec
+  UnitTestFrameworkPkg/UnitTestFrameworkPkg.dec
+  PolicyServicePkg/PolicyServicePkg.dec
+
+[LibraryClasses]
+  GoogleTestLib
+
+[BuildOptions]
+  MSFT:*_*_*_CC_FLAGS = /EHsc

PolicyServicePkg/Test/PolicyServicePkgHostTest.dsc

@@ -25,3 +25,7 @@
   PolicyServicePkg/PolicyService/DxeMm/UnitTest/DxeMmPolicyUnitTest.inf
   PolicyServicePkg/PolicyService/Pei/UnitTest/PeiPolicyUnitTest.inf
 
+  #
+  # Build HOST_APPLICATION Libraries With GoogleTest
+  #
+  PolicyServicePkg/Test/Mock/Library/GoogleTest/MockPolicyLibCommon/MockPolicyLibCommon.inf