Bug 1254858: P7. Add logging if libmozav can't be found. r=kentuckyfriedtakahe

MozReview-Commit-ID: C4m54MMJdr

--HG--
extra : rebase_source : 4cb6bfddbc4b2f0b0e26a6d6c09754b47167c87c

dom/media/platforms/ffmpeg/ffvpx/FFVPXRuntimeLinker.cpp

@@ -32,7 +32,11 @@ MozAVLink(const char* aName)
   PRLibSpec lspec;
   lspec.type = PR_LibSpec_Pathname;
   lspec.value.pathname = aName;
-  return PR_LoadLibraryWithFlags(lspec, PR_LD_NOW | PR_LD_LOCAL);
+  PRLibrary* lib = PR_LoadLibraryWithFlags(lspec, PR_LD_NOW | PR_LD_LOCAL);
+  if (!lib) {
+    FFMPEG_LOG("unable to load library %s", aName);
+  }
+  return lib;
 }
 
 /* static */ bool