[Frontend] Internalize createDependencyTracker

Expand the FrontendOptions to allow the enabling
of the dependency tracker for non-system
dependencies, and switch the previous clients of
`createDependencyTracker` over to using this
option. This ensures that the dependency tracker
is now set only during `CompilerInstance::setup`.

lib/FrontendTool/FrontendTool.cpp

@@ -793,7 +793,7 @@ static bool buildModuleFromInterface(CompilerInstance &Instance) {
       PrebuiltCachePath, Invocation.getModuleName(), InputPath,
       Invocation.getOutputFilename(),
       FEOpts.SerializeModuleInterfaceDependencyHashes,
-      FEOpts.TrackSystemDeps, LoaderOpts);
+      FEOpts.shouldTrackSystemDependencies(), LoaderOpts);
 }
 
 static bool compileLLVMIR(CompilerInstance &Instance) {