C#: Convert libraries to use matchesHandle instead of getLabel.

Author: calumgrant

csharp/ql/src/semmle/code/csharp/commons/Disposal.qll

@@ -38,7 +38,7 @@ private predicate disposedCSharpVariable(Variable variable) {
   // A C# parameter is disposed if its corresponding CIL parameter is disposed
   exists(CIL::Method m, CIL::Parameter p, int i |
     disposedCilVariable(p) and p = m.getRawParameter(i) |
-    variable = any(Callable c2 | c2.getLabel() = m.getLabel()).getRawParameter(i)
+    variable = any(Callable c2 | c2.matchesHandle(m)).getRawParameter(i)
   )
   or
   // Call to a method that disposes it

csharp/ql/src/semmle/code/csharp/dataflow/DataFlow.qll

@@ -627,14 +627,14 @@ module DataFlow {
           result = sourceDecl
         else if sourceDecl instanceof CIL::Callable then
           // CIL callable with C# implementation in the database
-          sourceDecl.getLabel() = result.(Callable).getLabel()
+          sourceDecl.matchesHandle(result.(Callable))
           or
           // CIL callable without C# implementation in the database
-          not sourceDecl.getLabel() = any(Callable k).getLabel() and
+          not sourceDecl.matchesHandle(any(Callable k)) and
           result = sourceDecl
         else
           // C# callable without C# implementation in the database
-          sourceDecl.getLabel() = result.(CIL::Callable).getLabel()
+          sourceDecl.matchesHandle(result.(CIL::Callable))
       )
     }