Cherry-pick r44373, r44378, and r44275.

pkg/analyzer/test/generated/engine_test.dart

Index: pkg/analyzer/test/generated/engine_test.dart
diff --git a/pkg/analyzer/test/generated/engine_test.dart b/pkg/analyzer/test/generated/engine_test.dart
index 0949de758143a98c4701ffb06cc58f992ee59577..2b2c5f3a3c4f6e02534da1050613ed69a9f73a18 100644
--- a/pkg/analyzer/test/generated/engine_test.dart
+++ b/pkg/analyzer/test/generated/engine_test.dart
@@ -5479,11 +5479,16 @@ class TestAnalysisContext implements InternalAnalysisContext {
   }
 
   @override
+  List<Source> get sources {
+    fail("Unexpected invocation of sources");
+    return null;
+  }
+
+  @override
   AnalysisContextStatistics get statistics {
     fail("Unexpected invocation of getStatistics");
     return null;
   }
-
   @override
   TypeProvider get typeProvider {
     fail("Unexpected invocation of getTypeProvider");
@@ -5734,6 +5739,7 @@ class TestAnalysisContext implements InternalAnalysisContext {
       int oldLength, int newLength) {
     fail("Unexpected invocation of setChangedContents");
   }
+
   @override
   void setContents(Source source, String contents) {
     fail("Unexpected invocation of setContents");