Validate not only errors, but also warnings.

Change-Id: I2c03711061ccd40d1609cf9148f3169b4df847d5
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/135600
Reviewed-by: Bob Nystrom <rnystrom@google.com>
Commit-Queue: Konstantin Shcheglov <scheglov@google.com>

pkg/test_runner/lib/src/command_output.dart

@@ -1193,7 +1193,10 @@ mixin _StaticErrorOutput on CommandOutput {
             ? error.isAnalyzer
             : error.isCfe);
 
-    var validation = StaticError.validateExpectations(expected, errors);
+    var validation = StaticError.validateExpectations(
+      expected,
+      [...errors, ...warnings],
+    );
     if (validation == null) return Expectation.pass;
 
     writer?.subsection("static error failures");

tests/language_2/variable/inst_field_initializer1_test.dart

@@ -10,6 +10,8 @@ class A {
   //         ^
   // [analyzer] COMPILE_TIME_ERROR.IMPLICIT_THIS_REFERENCE_IN_INITIALIZER
   // [cfe] Can't access 'this' in a field initializer to read 'x'.
+  //         ^
+  // [analyzer] STATIC_WARNING.TOP_LEVEL_INSTANCE_GETTER
 }
 
 void main() {