Issue 6077. warn when importing dart:mirrors

compiler/java/com/google/dart/compiler/DartCompiler.java

Index: compiler/java/com/google/dart/compiler/DartCompiler.java
diff --git a/compiler/java/com/google/dart/compiler/DartCompiler.java b/compiler/java/com/google/dart/compiler/DartCompiler.java
index 751c7f6f0100703dd3c4c712455d1bff08956e40..c044940b433c925ca9e7c016cef3fa48a449bfa9 100644
--- a/compiler/java/com/google/dart/compiler/DartCompiler.java
+++ b/compiler/java/com/google/dart/compiler/DartCompiler.java
@@ -649,9 +649,15 @@ public class DartCompiler {
         boolean hasIO = false;
         boolean hasHTML = false;
         for (LibraryNode importNode : lib.getImportPaths()) {
+          String libSpec = importNode.getText();
           String prefix = importNode.getPrefix();
-          hasIO |= "dart:io".equals(importNode.getText());
-          hasHTML |= "dart:html".equals(importNode.getText());
+          hasIO |= "dart:io".equals(libSpec);
+          hasHTML |= "dart:html".equals(libSpec);
+          // "dart:mirrors" are not done yet
+          if ("dart:mirrors".equals(libSpec)) {
+            context.onError(new DartCompilationError(importNode,
+                DartCompilerErrorCode.MIRRORS_NOT_FULLY_IMPLEMENTED));
+          }
           // validate import prefix
           if (DartParser.PSEUDO_KEYWORDS_SET.contains(prefix)) {
             context.onError(new DartCompilationError(importNode.getSourceInfo(),