base: Remove the string logging from CHECK().

chrome/test/base/extension_load_waiter_one_shot.cc

Index: chrome/test/base/extension_load_waiter_one_shot.cc
diff --git a/chrome/test/base/extension_load_waiter_one_shot.cc b/chrome/test/base/extension_load_waiter_one_shot.cc
index e0487b03393077cff724786550b6db801ccb3433..1759a91a67c03db8b194431596f64c11cfc83f1b 100644
--- a/chrome/test/base/extension_load_waiter_one_shot.cc
+++ b/chrome/test/base/extension_load_waiter_one_shot.cc
@@ -20,8 +20,8 @@ ExtensionLoadWaiterOneShot::~ExtensionLoadWaiterOneShot() {
 
 void ExtensionLoadWaiterOneShot::WaitForExtension(const char* extension_id,
                                   const base::Closure& load_cb) {
-  CHECK(!extension_id_) <<
-      "ExtensionLoadWaiterOneShot should only be used once.";
+  // ExtensionLoadWaiterOneShot should only be used once.
+  CHECK(!extension_id_);
   extension_id_ = extension_id;
   load_looper_ = new content::MessageLoopRunner();
   registrar_.Add(this,