Add a new (simple) StringMap::clear method, patch by Pratik

Solanki!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53008 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/ADT/StringMap.h

@@ -333,6 +333,12 @@ public:
     return true;
   }
 
+  // clear - Empties out the StringMap
+  void clear() {
+    while (!empty())
+      erase(begin());
+  }
+
   /// GetOrCreateValue - Look up the specified key in the table.  If a value
   /// exists, return it.  Otherwise, default construct a value, insert it, and
   /// return.