Bug 840177 - Part 5: Add observer notification for keyword searches; r=gavin

The intent is for this to be captured by Firefox Health Report.

docshell/base/nsDefaultURIFixup.cpp

@@ -383,6 +383,20 @@ NS_IMETHODIMP nsDefaultURIFixup::KeywordToURI(const nsACString& aKeyword,
                     return NS_ERROR_NOT_AVAILABLE;
                 }
 
+                // This notification is meant for Firefox Health Report so it
+                // can increment counts from the search engine. The assumption
+                // here is that this keyword/submission will eventually result
+                // in a search. Since we only generate a URI here, there is the
+                // possibility we'll increment the counter without actually
+                // incurring a search. A robust solution would involve currying
+                // the search engine's name through various function calls.
+                nsCOMPtr<nsIObserverService> obsSvc = mozilla::services::GetObserverService();
+                if (obsSvc) {
+                  nsAutoString name;
+                  defaultEngine->GetName(name);
+                  obsSvc->NotifyObservers(nullptr, "keyword-search", name.get());
+                }
+
                 return submission->GetUri(aURI);
             }
         }

docshell/test/browser/Makefile.in

@@ -68,6 +68,7 @@ MOCHITEST_BROWSER_FILES =	\
 		file_bug234628-11.html \
 		file_bug234628-11-child.xhtml \
 		file_bug234628-11-child.xhtml^headers^ \
+		browser_search_notification.js \
 		$(NULL)
 
 include $(topsrcdir)/config/rules.mk

docshell/test/browser/browser_search_notification.js

@@ -0,0 +1,29 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+function test() {
+  waitForExplicitFinish();
+
+  let tab = gBrowser.addTab();
+  gBrowser.selectedTab = tab;
+
+  function observer(subject, topic, data) {
+    Services.obs.removeObserver(observer, "keyword-search");
+    is(topic, "keyword-search", "Got keyword-search notification");
+
+    let engine = Services.search.originalDefaultEngine;
+    ok(engine, "Have default search engine.");
+    is(engine.name, data, "Notification data is engine name.");
+
+    executeSoon(function cleanup() {
+      gBrowser.removeTab(tab);
+      finish();
+    });
+  }
+
+  Services.obs.addObserver(observer, "keyword-search", false);
+
+  gURLBar.value = "firefox health report";
+  gURLBar.handleCommand();
+}
+