Remove CharStream from SourceLocation.

tools/yulPhaser/Program.h

@@ -35,6 +35,7 @@ namespace solidity::langutil
 {
 
 class CharStream;
+class Scanner;
 
 }
 
@@ -47,13 +48,6 @@ struct CodeWeights;
 
 }
 
-namespace std
-{
-
-std::ostream& operator<<(std::ostream& _outputStream, solidity::langutil::ErrorList const& _errors);
-
-}
-
 namespace solidity::phaser
 {