Update comments

Author: elsh

include/swift/Frontend/Frontend.h

@@ -309,6 +309,9 @@ class CompilerInvocation {
     return FrontendOpts.ModuleName;
   }
 
+  /// Sets module alias map with string args passed in via `-module-alias`. This assumes
+  /// the args are valid strings; full validation of input args for module aliasing is done at
+  /// \c ArgsToFrontendOptionsConverter::computeModulealiases.
   void setModuleAliasMap(std::vector<std::string> args);
 
   std::string getOutputFilename() const {

lib/Frontend/CompilerInvocation.cpp

@@ -262,9 +262,6 @@ void CompilerInvocation::setSDKPath(const std::string &Path) {
   updateRuntimeLibraryPaths(SearchPathOpts, LangOpts.Target);
 }
 
-// This assumes the param args contains valid strings for module
-// aliasing. The full validation of input for aliasing is done at
-// ArgsToFrontendOptionsConverter::computeModulealiases.
 void CompilerInvocation::setModuleAliasMap(std::vector<std::string> args) {
   // ModuleAliasMap should initially be empty as setting
   // it should be called only once