FEXCore: Expose DiskCache version to the frontend

With a comment about includes currently being incorrectly shared to the
frontend and needs to get resolved.

FEXCore/Source/Interface/Core/DiskCache.cpp

@@ -636,6 +636,9 @@ namespace DiskCache {
     return true;
   }
 
+  uint16_t GetFormatVersion() {
+    return FormatVersion;
+  }
 } // namespace DiskCache
 
 } // namespace FEXCore

FEXCore/include/FEXCore/Core/DiskCache.h

@@ -177,7 +177,6 @@ namespace DiskCache {
     uint64_t MakeBlobKey(const uint64_t ModuleOffset);
 
     FEXCore::Context::ContextImpl* CTX;
-    static const uint16_t FormatVersion = 3;
     XXH128_hash_t BucketHash;
     fextl::vector<fextl::unique_ptr<IndexedDB>> ROCacheDBs;
     fextl::unique_ptr<IndexedDB> RWCacheDB;
@@ -196,6 +195,11 @@ namespace DiskCache {
     FEX_CONFIG_OPT(RODBNames, DISKCACHERODBNAMES);
   };
 
+  // TODO: This header is in global installed header path, but uses internal headers.
+  // Migrate this once that is fixed.
+  static constexpr uint16_t FormatVersion = 3;
+  FEX_DEFAULT_VISIBILITY uint16_t GetFormatVersion();
+
 } // namespace DiskCache
 
-} // namespace FEXCore
+} // namespace FEXCore