Fix recently introduced strong-mode errors

pkg/analyzer/test/src/task/inputs_test.dart

Index: pkg/analyzer/test/src/task/inputs_test.dart
diff --git a/pkg/analyzer/test/src/task/inputs_test.dart b/pkg/analyzer/test/src/task/inputs_test.dart
index ed4ecb338f2ae596f480b1aa42b01e7dfd64db92..33bcbee53f38e5920391d359fb276100bd4a4f6f 100644
--- a/pkg/analyzer/test/src/task/inputs_test.dart
+++ b/pkg/analyzer/test/src/task/inputs_test.dart
@@ -123,7 +123,7 @@ class ConstantTaskInputTest extends EngineTestCase {
 @reflectiveTest
 class ListTaskInputImplTest extends EngineTestCase {
   static final AnalysisTarget target = new TestSource();
-  static final result1 =
+  static final ResultDescriptor<List<AnalysisTarget>> result1 =
       new ResultDescriptorImpl<List<AnalysisTarget>>('result1', null);
   static final result2 = new ResultDescriptorImpl<int>('result2', null);
 
@@ -897,7 +897,7 @@ class TopLevelTaskInputBuilderTest extends EngineTestCase {
 
   test_currentResult_afterTwoMoveNext_withConstantInput() {
     ConstantTaskInput<int> constantInput = new ConstantTaskInput<int>(11);
-    Map<String, TaskInput> inputDescriptors = {
+    Map<String, TaskInput> inputDescriptors = <String, TaskInput>{
       'one': input1,
       'constant': constantInput,
       'two': input2
@@ -947,7 +947,7 @@ class TopLevelTaskInputBuilderTest extends EngineTestCase {
 
   test_currentTarget_afterTwoMoveNext_withConstantInput() {
     ConstantTaskInput<int> constantInput = new ConstantTaskInput<int>(11);
-    Map<String, TaskInput> inputDescriptors = {
+    Map<String, TaskInput> inputDescriptors = <String, TaskInput>{
       'one': input1,
       'constant': constantInput,
       'two': input2