Refactor oemcrypto mock into stand alone reference code

Merge from Widevine repo of http://go/wvgerrit/46204
Refactor utility code - split the mock, step 1

Merge from Widevine repo of http://go/wvgerrit/46205
Move some OEMCrypto types to common header - split the mock, step 2

Merge from Widevine repo of http://go/wvgerrit/46206
Split mock into two -- step 3

Merge from Widevine repo of http://go/wvgerrit/47460
Split the mock into two -- step 3.5

The CL moves several files used by oemcrypto and cdm into a common
subdirectory, so that it may more easily be shared with partners.

The CORE_DISALLOW_COPY_AND_ASSIGN macro was moved to its own header in
the util/include directory.

This CL removes some references to the mock from other code, and puts
some constants and types, such as the definition of the keybox, into a
header in oemcrypto.

Test: tested as part of http://go/ag/4674759
bug: 76393338
Change-Id: I75b4bde7062ed8ee572c97ebc2f4da018f4be0c9

libwvdrmengine/oemcrypto/test/oemcrypto_test_android.cpp

@@ -142,7 +142,6 @@ TEST_F(OEMCryptoAndroidOCTest, MinVersionNumber13) {
   ASSERT_GE(version, 13u);
 }
 
-#if 0  // TODO(b/64001862)
 // These tests are required for Pi MR1 Android devices.
 class OEMCryptoAndroidPiMR1Test : public OEMCryptoAndroidOCTest {};
 
@@ -150,6 +149,5 @@ TEST_F(OEMCryptoAndroidPiMR1Test, MinVersionNumber14) {
   uint32_t version = OEMCrypto_APIVersion();
   ASSERT_GE(version, 14u);
 }
-#endif
 
 }  // namespace wvoec