Try to reduce the flankness of the PPAPI UI tests.

ppapi/tests/testing_instance.h

Index: ppapi/tests/testing_instance.h
===================================================================
--- ppapi/tests/testing_instance.h	(revision 97356)
+++ ppapi/tests/testing_instance.h	(working copy)
@@ -17,6 +17,20 @@
 
 class TestCase;
 
+// How signaling works:
+//
+// We want to signal to the Chrome UI test hardness that we're making progress

[polina, 2011/08/22 23:53:58]

a file path could be useful here

+// and when we're done. The easiest thing in the UI test infrastructure is to
+// wait for a cookie to become nonempty. We don't want to have a big wait for
+// all tests in a TestCase since they can take a while and it might timeout.
+// So we set a series of cookies with an incrementing number in the name.

[polina, 2011/08/22 23:53:58]

please add something like "per every test run within a TestCase".

+//
+// If the value of the cookie is "..." then that tells the test runner that
+// the test is progressing. It then waits for the next numbered cookie until

[polina, 2011/08/22 23:53:58]

TestCase is progressing

+// it either times out or the value is something other than "...". In this

[polina, 2011/08/22 23:53:58]

Just to confirm, by sending more messages more often, we reduced the likelihood
of a time-out for a successful run. However, if one test run is misbehaving and
timing out, we still get the same fail-all behavior and don't get to skip over
to left-over tests? A clarification in the comments would be helpful.

+// case, the value will be either "PASS" or "FAIL [optional message]".

[polina, 2011/08/22 23:53:58]

please add something like "corresponding to the outcome of the entire TestCase"

+//
+//
 // In trusted builds, we use InstancePrivate and allow tests that use
 // synchronous scripting. NaCl does not support synchronous scripting.
 class TestingInstance : public
@@ -81,6 +95,8 @@
   // Appends the given HTML string to the console in the document.
   void LogHTML(const std::string& html);
 
+  void ReportProgress(const std::string& progress_value);
+
   // Sets the given cookie in the current document.
   void SetCookie(const std::string& name, const std::string& value);
 
@@ -89,6 +105,10 @@
   // Owning pointer to the current test case. Valid after Init has been called.
   TestCase* current_case_;
 
+  // The current step we're on starting at 0. This is incremented every time we
+  // report progress via a cookie. See comment above the class.
+  int progress_number_;

[polina, 2011/08/22 23:53:58]

progress_cookie_number_?

+
   // Set once the tests are run so we know not to re-run when the view is sized.
   bool executed_tests_;