Gardening: Mark io/http_basic_test slow. Add debug prints into io/process_start_exception_test.

tests/standalone/io/process_start_exception_test.dart

Index: tests/standalone/io/process_start_exception_test.dart
diff --git a/tests/standalone/io/process_start_exception_test.dart b/tests/standalone/io/process_start_exception_test.dart
index a1f891e34fb5ad5a4ddccfcfcd100c4f84d4e8d1..2c30400882ce4eaad02304452e4f737da6686358 100644
--- a/tests/standalone/io/process_start_exception_test.dart
+++ b/tests/standalone/io/process_start_exception_test.dart
@@ -8,6 +8,26 @@ import "package:expect/expect.dart";
 import 'dart:async';
 import 'dart:io';
 
+// Constants from errno.h
+const ENOENT = 2;
+const EACCES = 13;
+
+// TODO(http://dartbug.com/28299) This code is added in attempt to collect more
+// information about the flakyness this test experiences on Android bots:
+// sometimes the test fails because we get EACCES instead of ENOENT error
+// from the OS.
+checkForAccessError(error) {
+  if (error.errorCode == EACCES) {
+    report(obj) {
+      final stat = obj.statSync();
+      print("${obj} | ${stat.type} | ${stat.modeString()}");
+    }
+
+    report(Directory.current);
+    report(new File("__path_to_something_that_should_not_exist__"));
+  }
+}
+
 testStartError() {
   Future<Process> processFuture =
       Process.start("__path_to_something_that_should_not_exist__",
@@ -15,7 +35,8 @@ testStartError() {
   processFuture.then((p) => Expect.fail('got process despite start error'))
   .catchError((error) {
     Expect.isTrue(error is ProcessException);
-    Expect.equals(2, error.errorCode, error.toString());
+    checkForAccessError(error);
+    Expect.equals(ENOENT, error.errorCode, error.toString());
   });
 }
 
@@ -27,7 +48,8 @@ testRunError() {
   processFuture.then((result) => Expect.fail("exit handler called"))
   .catchError((error) {
     Expect.isTrue(error is ProcessException);
-    Expect.equals(2, error.errorCode, error.toString());
+    checkForAccessError(error);
+    Expect.equals(ENOENT, error.errorCode, error.toString());
   });
 }