[llvm/CAS] More fixes for the non-LLVM_ENABLE_ONDISK_CAS build

Author: akyrtzi

llvm/lib/CAS/OnDiskHashMappedTrie.cpp

@@ -1319,6 +1319,10 @@ void OnDiskHashMappedTrie::print(
   report_fatal_error("not supported");
 }
 
+size_t OnDiskHashMappedTrie::size() const {
+  report_fatal_error("not supported");
+}
+
 struct OnDiskDataAllocator::ImplType {};
 
 Expected<OnDiskDataAllocator> OnDiskDataAllocator::create(
@@ -1336,6 +1340,14 @@ const char *OnDiskDataAllocator::beginData(FileOffset Offset) const {
   report_fatal_error("not supported");
 }
 
+MutableArrayRef<uint8_t> OnDiskDataAllocator::getUserHeader() {
+  report_fatal_error("not supported");
+}
+
+size_t OnDiskDataAllocator::size() const {
+  report_fatal_error("not supported");
+}
+
 #endif // LLVM_ENABLE_ONDISK_CAS
 
 OnDiskHashMappedTrie::OnDiskHashMappedTrie(std::unique_ptr<ImplType> Impl)