Add some log messages to investigate WebRequestBlocking test failures.

chrome/browser/extensions/extension_webrequest_apitest.cc

Index: chrome/browser/extensions/extension_webrequest_apitest.cc
diff --git a/chrome/browser/extensions/extension_webrequest_apitest.cc b/chrome/browser/extensions/extension_webrequest_apitest.cc
index 09384fcb3a56723510c3cbc18001e224efe3d1bd..8576d3ffd3bd623473d8dcfdbe0c95ba38c4e3b9 100644
--- a/chrome/browser/extensions/extension_webrequest_apitest.cc
+++ b/chrome/browser/extensions/extension_webrequest_apitest.cc
@@ -76,14 +76,7 @@ IN_PROC_BROWSER_TEST_F(ExtensionWebRequestApiTest, WebRequestComplex) {
       message_;
 }
 
-#if defined(OS_CHROMEOS) || defined(OS_MACOSX) || defined(OS_LINUX)
-// Times out: http://crbug.com/91715
-#define MAYBE_WebRequestBlocking DISABLED_WebRequestBlocking
-#else
-#define MAYBE_WebRequestBlocking WebRequestBlocking
-#endif
-
-IN_PROC_BROWSER_TEST_F(ExtensionWebRequestApiTest, MAYBE_WebRequestBlocking) {
+IN_PROC_BROWSER_TEST_F(ExtensionWebRequestApiTest, WebRequestBlocking) {
   CommandLine::ForCurrentProcess()->AppendSwitch(
       switches::kEnableExperimentalExtensionApis);