Misc Windows fixes.

(This is a merge of http://go/wvgerrit/70324)

- Add build settings for Windows.
- Conditionally add pthread.
- Add dummy DLLMain method.
- Fix #if checks for Windows.
- Remove designated initializers which aren't supported in MSVC.
- Remove variable length array.

Test: Android Unit Tests
Bug: 122953649
Change-Id: I14f16e7ce4b3ff17ee0139ea6c2f7243ae999aa1

libwvdrmengine/oemcrypto/ref/src/oemcrypto_engine_device_properties_cert.cpp

@@ -15,8 +15,8 @@ namespace wvoec_ref {
 
 class CertOnlyCryptoEngine : public CryptoEngine {
  public:
-  explicit CertOnlyCryptoEngine(std::unique_ptr<wvcdm::FileSystem> file_system)
-      : CryptoEngine(file_system) {}
+  explicit CertOnlyCryptoEngine(std::unique_ptr<wvcdm::FileSystem>&& file_system)
+      : CryptoEngine(std::move(file_system)) {}
 
   bool config_local_display_only() { return true; }
 
@@ -30,8 +30,8 @@ class CertOnlyCryptoEngine : public CryptoEngine {
 };
 
 CryptoEngine* CryptoEngine::MakeCryptoEngine(
-    std::unique_ptr<wvcdm::FileSystem> file_system) {
-  return new CertOnlyCryptoEngine(file_system);
+    std::unique_ptr<wvcdm::FileSystem>&& file_system) {
+  return new CertOnlyCryptoEngine(std::move(file_system));
 }
 
 }  // namespace wvoec_ref