Collect call site information and use that for estimating parameter types

lib/compiler/implementation/universe.dart

Index: lib/compiler/implementation/universe.dart
diff --git a/lib/compiler/implementation/universe.dart b/lib/compiler/implementation/universe.dart
index ebf742aa5c177e161b6adb3a7909fba739479279..aa1d89725de8cae8366da80346d5c33bea4ee19b 100644
--- a/lib/compiler/implementation/universe.dart
+++ b/lib/compiler/implementation/universe.dart
@@ -283,7 +283,7 @@ class Selector implements Hashable {
     return orderedNamedArguments;
   }
 
-  toString() => '$kind $argumentCount';
+  toString() => 'Selector($kind, $argumentCount)';
 }
 
 class TypedSelector extends Selector {
@@ -353,4 +353,6 @@ class TypedSelector extends Selector {
     if (other.receiverType !== receiverType) return false;
     return super == other;
   }
+
+  toString() => 'TypedSelector($kind, $receiverType, $argumentCount)';
 }