Add traces temporarily to track down flakiness in test.

chrome/browser/extensions/extension_toolbar_model.cc

Index: chrome/browser/extensions/extension_toolbar_model.cc
diff --git a/chrome/browser/extensions/extension_toolbar_model.cc b/chrome/browser/extensions/extension_toolbar_model.cc
index 7779514cb8cb579f43f59f9556e2001e58b176a9..92ee8dea29628bcb6266b224549bb74d47cf4502 100644
--- a/chrome/browser/extensions/extension_toolbar_model.cc
+++ b/chrome/browser/extensions/extension_toolbar_model.cc
@@ -158,8 +158,13 @@ ExtensionToolbarModel::Action ExtensionToolbarModel::ExecuteBrowserAction(
 }
 
 void ExtensionToolbarModel::SetVisibleIconCount(int count) {
+  LOG(ERROR) << "visible_icon_count_ before: " << visible_icon_count_;
   visible_icon_count_ =
       count == static_cast<int>(toolbar_items_.size()) ? -1 : count;
+  LOG(ERROR) << "SetVisibleIconCount "
+             << count << " == " << toolbar_items_.size() << " -> "
+             << visible_icon_count_ << " "
+             << "is_highlighting: " << is_highlighting_;
   // Only set the prefs if we're not in highlight mode. Highlight mode is
   // designed to be a transitory state, and should not persist across browser
   // restarts (though it may be re-entered).
@@ -171,16 +176,23 @@ void ExtensionToolbarModel::SetVisibleIconCount(int count) {
 void ExtensionToolbarModel::OnExtensionLoaded(
     content::BrowserContext* browser_context,
     const Extension* extension) {
+  LOG(ERROR) << "Loading extension";
+
   // We don't want to add the same extension twice. It may have already been
   // added by EXTENSION_BROWSER_ACTION_VISIBILITY_CHANGED below, if the user
   // hides the browser action and then disables and enables the extension.
   for (size_t i = 0; i < toolbar_items_.size(); i++) {
-    if (toolbar_items_[i].get() == extension)
+    if (toolbar_items_[i].get() == extension) {
+      LOG(ERROR) << "... but returning early";
       return;
+    }
   }
   if (ExtensionActionAPI::GetBrowserActionVisibility(extension_prefs_,
                                                      extension->id())) {
+    LOG(ERROR) << "Adding extensions";
     AddExtension(extension);
+  } else {
+    LOG(ERROR) << "NOT visible";
   }
 }
 
@@ -218,8 +230,10 @@ void ExtensionToolbarModel::Observe(
           ExtensionRegistry::EVERYTHING);
   if (ExtensionActionAPI::GetBrowserActionVisibility(extension_prefs_,
                                                      extension->id())) {
+    LOG(ERROR) << "Adding extension";
     AddExtension(extension);
   } else {
+    LOG(ERROR) << "Removing extension";
     RemoveExtension(extension);
   }
 }