Bug 1592797 - Fix MediaKeys linker error exposed with different optimization flags r=edgar

Seeing this linker error when building with optimization flags -O2 and others:
.../mozilla-central/dom/media/eme/mediadrm/MediaDrmCDMProxy.cpp:297: error: undefined reference to 'void mozilla::dom::MediaKeys::ResolvePromiseWithResult<bool>(unsigned int, bool const&)'

This patch moves the template definition from dom/media/eme/MediaKeys.cpp to dom/media/eme/MediaKeys.h

Differential Revision: https://phabricator.services.mozilla.com/D51188

--HG--
extra : moz-landing-system : lando

dom/media/eme/MediaKeys.cpp

@@ -569,16 +569,6 @@ void MediaKeys::OnSessionLoaded(PromiseId aId, bool aSuccess) {
   ResolvePromiseWithResult(aId, aSuccess);
 }
 
-template <typename T>
-void MediaKeys::ResolvePromiseWithResult(PromiseId aId, const T& aResult) {
-  RefPtr<DetailedPromise> promise(RetrievePromise(aId));
-  if (!promise) {
-    return;
-  }
-
-  promise->MaybeResolve(aResult);
-}
-
 void MediaKeys::OnSessionClosed(MediaKeySession* aSession) {
   nsAutoString id;
   aSession->GetSessionId(id);

dom/media/eme/MediaKeys.h

@@ -149,7 +149,13 @@ class MediaKeys final : public nsIDocumentActivity,
                                    dom::MediaKeyStatus aMediaKeyStatus);
 
   template <typename T>
-  void ResolvePromiseWithResult(PromiseId aId, const T& aResult);
+  void ResolvePromiseWithResult(PromiseId aId, const T& aResult) {
+    RefPtr<DetailedPromise> promise(RetrievePromise(aId));
+    if (!promise) {
+      return;
+    }
+    promise->MaybeResolve(aResult);
+  }
 
  private:
   // Instantiate CDMProxy instance.