Removed debugging information in the testing infrastructure and added a warning

tools/testing/dart/test_runner.dart

Index: tools/testing/dart/test_runner.dart
diff --git a/tools/testing/dart/test_runner.dart b/tools/testing/dart/test_runner.dart
index e9d5683832cff106e258d24c71920898fd1a14af..aa9980a5d1b7f48555816a12d43064349da6c23b 100644
--- a/tools/testing/dart/test_runner.dart
+++ b/tools/testing/dart/test_runner.dart
@@ -631,7 +631,7 @@ class BrowserCommandOutputImpl extends CommandOutputImpl {
         if ((testCase as BrowserTestCase).numRetries > 0) {
           requestRetry = true;
         }
-        printDebug("Test failure because of missing XDisplay");
+        print("Warning: Test failure because of missing XDisplay");
         return true;
       }
     }
@@ -674,33 +674,20 @@ class BrowserCommandOutputImpl extends CommandOutputImpl {
                 bytesNewLine.length;
             var endPosition = stdout.length - bytesEOF.length;
 
-            var _failed = !areByteArraysEqual(expectedContent,
-                                              0,
-                                              stdout,
-                                              startPosition,
-                                              endPosition - startPosition);
-            if (_failed) {
-              printDebug("Test failure because command.expectedOutputFile "
-                         "doesn't match stdout of DRT");
-            }
-            return _failed;
+            return !areByteArraysEqual(expectedContent,
+                                       0,
+                                       stdout,
+                                       startPosition,
+                                       endPosition - startPosition);
           }
         }
-        printDebug("Test failure because we didn't find 'Content-Length' in the"
-                   " DRT output");
         return true;
       } else {
-        var _failed = !areByteArraysEqual(expectedContent, 0,
-                                          stdout, 0,
-                                          stdout.length);
-        if (_failed) {
-          printDebug("Test failure because command.expectedOutputFile doesn't "
-                     "match stdout of DRT");
-        }
-        return _failed;
+        return !areByteArraysEqual(expectedContent, 0,
+                                   stdout, 0,
+                                   stdout.length);
       }
     }
-    printDebug("Test failure because command.expectedOutputFile doesn't exist");
     return true;
   }
 
@@ -716,29 +703,17 @@ class BrowserCommandOutputImpl extends CommandOutputImpl {
           break;
         case 'PASS':
           if (has_content_type) {
-            var _failed = (exitCode != 0 && !hasCrashed);
-            if (_failed) {
-              printDebug("Test failure because '(exitCode != 0 && !hasCrashed) "
-                         "was true");
+            if (exitCode != 0) {
+              print("Warning: All tests passed, but exitCode != 0 "
+                    "(${testCase.displayName})");
             }
-            return _failed;
+            return (exitCode != 0 && !hasCrashed);
           }
           break;
       }
     }
-    printDebug("Test failure because content-type: text/plain + PASS was not "
-               "found");
     return true;
   }
-
-  void printDebug(String msg) {
-    print("");
-    print("DEBUG(infrastructure): $msg");
-    print("DEBUG(infrastructure): cmd.executable:  '${command.executable}'");
-    print("DEBUG(infrastructure): cmd.arguments:   '${command.arguments}'");
-    print("DEBUG(infrastructure): cmd.environment: '${command.environment}'");
-    print("");
-  }
 }
 
 // The static analyzer does not actually execute code, so