Make analyzer more strong mode compliant

pkg/analyzer/lib/task/model.dart

Index: pkg/analyzer/lib/task/model.dart
diff --git a/pkg/analyzer/lib/task/model.dart b/pkg/analyzer/lib/task/model.dart
index be60b784725230f3f6d1b67e2ffd1894e6508330..fbaf348b055844cf828a77376486ef32dacdac7a 100644
--- a/pkg/analyzer/lib/task/model.dart
+++ b/pkg/analyzer/lib/task/model.dart
@@ -185,11 +185,11 @@ abstract class AnalysisTask {
    * Return the value of the input with the given [name]. Throw an exception if
    * the input value is not defined.
    */
-  Object getRequiredInput(String name) {
+  Object/*=E*/ getRequiredInput/*<E>*/(String name) {
     if (inputs == null || !inputs.containsKey(name)) {
       throw new AnalysisException("Could not $description: missing $name");
     }
-    return inputs[name];
+    return inputs[name] as Object/*=E*/;
   }
 
   /**