Ignore 'dart-ext:' scheme, allow 'native' in such files

compiler/javatests/com/google/dart/compiler/end2end/inc/IncrementalCompilation2Test.java

Index: compiler/javatests/com/google/dart/compiler/end2end/inc/IncrementalCompilation2Test.java
diff --git a/compiler/javatests/com/google/dart/compiler/end2end/inc/IncrementalCompilation2Test.java b/compiler/javatests/com/google/dart/compiler/end2end/inc/IncrementalCompilation2Test.java
index 109aa5f5ff8e7aa6cee06bf607db497b46f3de63..c13c42aa6b028425f360dc6d304a2c40bbbaf9c4 100644
--- a/compiler/javatests/com/google/dart/compiler/end2end/inc/IncrementalCompilation2Test.java
+++ b/compiler/javatests/com/google/dart/compiler/end2end/inc/IncrementalCompilation2Test.java
@@ -1262,7 +1262,7 @@ public class IncrementalCompilation2Test extends CompilerTestCase {
     compile();
     ErrorExpectation.assertErrors(errors);
   }
-  
+
   /**
    * Investigation of failing "language/ct_const4_test".
    */
@@ -1287,6 +1287,46 @@ public class IncrementalCompilation2Test extends CompilerTestCase {
     assertErrors(errors);
   }
 
+  /**
+   * Internals of Dart use "dart-ext:" import scheme, and these libraries are allowed to use
+   * "native". New import syntax.
+   */
+  public void test_useNative_withDartExt_new() throws Exception {
+    appSource.setContent(
+        APP,
+        makeCode(
+            "// filler filler filler filler filler filler filler filler filler filler filler",
+            "library A;",
+            "import 'dart-ext:test_extension';",
+            "class A {",
+            "  static int ifNull(a, b) native 'TestExtension_IfNull';",
+            "}",
+            ""));
+    // do compile, no errors expected
+    compile();
+    assertErrors(errors);
+  }
+  
+  /**
+   * Internals of Dart use "dart-ext:" import scheme, and these libraries are allowed to use
+   * "native". Obsolete import syntax.
+   */
+  public void test_useNative_withDartExt_obsolete() throws Exception {
+    appSource.setContent(
+        APP,
+        makeCode(
+            "// filler filler filler filler filler filler filler filler filler filler filler",
+            "#library('A');",
+            "#import('dart-ext:test_extension');",
+            "class A {",
+            "  static int ifNull(a, b) native 'TestExtension_IfNull';",
+            "}",
+            ""));
+    // do compile, no errors expected
+    compile();
+    assertErrors(errors);
+  }
+
   private void assertAppBuilt() {
     didWrite(APP, EXTENSION_DEPS);
   }