Add an API to component_updater that asks to do an update check "now".

chrome/browser/component_updater/pnacl/pnacl_component_installer.cc

Index: chrome/browser/component_updater/pnacl/pnacl_component_installer.cc
diff --git a/chrome/browser/component_updater/pnacl/pnacl_component_installer.cc b/chrome/browser/component_updater/pnacl/pnacl_component_installer.cc
index f9cf2dad38a50780cf32dcc6528f733f3084f56f..d6ab1a0b44046a8311c17b4642b30245f554da7f 100644
--- a/chrome/browser/component_updater/pnacl/pnacl_component_installer.cc
+++ b/chrome/browser/component_updater/pnacl/pnacl_component_installer.cc
@@ -25,6 +25,11 @@ using content::BrowserThread;
 
 namespace {
 
+// If PNaCl isn't installed yet, but a user is running chrome with
+// --enable-pnacl, this is the amount of time to wait before starting
+// a background install.
+const int kInitialDelaySeconds = 10;
+
 // One of the Pnacl component files, for checking that expected files exist.
 // TODO(jvoung): perhaps replace this with a list of the expected files in the
 // manifest.json. Use that to check that everything is unpacked.
@@ -127,10 +132,6 @@ void SetPnaclHash(CrxComponent* component) {
 
 
 // If we don't have Pnacl installed, this is the version we claim.
-// TODO(jvoung): Is there a way to trick the configurator to ping the server
-// earlier if there are components that are not yet installed (version 0.0.0.0),
-// So that they will be available ASAP? Be careful not to hurt startup speed.
-// Make kNullVersion part of ComponentUpdater in that case, to avoid skew?
 const char kNullVersion[] = "0.0.0.0";
 
 // Pnacl components have the version encoded in the path itself:
@@ -315,6 +316,13 @@ bool PnaclComponentInstaller::Install(base::DictionaryValue* manifest,
 
 namespace {
 
+void DoCheckForUpdate(ComponentUpdateService* cus,
+                   const CrxComponent& pnacl) {
+  if (cus->CheckForUpdateSoon(pnacl) != ComponentUpdateService::kOk) {
+    LOG(WARNING) << "Pnacl check for update failed.";
+  }
+}
+
 // Finally, do the registration with the right version number.
 void FinishPnaclUpdateRegistration(ComponentUpdateService* cus,
                                    const Version& current_version) {
@@ -329,6 +337,17 @@ void FinishPnaclUpdateRegistration(ComponentUpdateService* cus,
   if (cus->RegisterComponent(pnacl) != ComponentUpdateService::kOk) {
     NOTREACHED() << "Pnacl component registration failed.";
   }
+
+  // If PNaCl is not yet installed but it is requested by --enable-pnacl,
+  // we want it to be available "soon", so kick off an update check

[cpu_(ooo_6.6-7.5), 2013/02/12 23:34:26]

wait, where is the command line check?

[jvoung (off chromium), 2013/02/12 23:38:37]

In chrome/browser/chrome_browser_main.cc, PNaCl is not registered at all if
--enable-pnacl isn't set, so it's a bit indirect:


void RegisterComponentsForUpdate(const CommandLine& command_line) {
  ComponentUpdateService* cus = g_browser_process->component_updater();
  if (!cus)
    return;
  // Registration can be before of after cus->Start() so it is ok to post
  // a task to the UI thread to do registration once you done the necessary
  // file IO to know you existing component version.
  RegisterRecoveryComponent(cus, g_browser_process->local_state());

  // ... stuff

  if (command_line.HasSwitch(switches::kEnablePnacl))
    RegisterPnaclComponent(cus);

  cus->Start();
}

+  // earlier than usual.
+  Version null_version(kNullVersion);
+  if (current_version.Equals(null_version)) {
+    BrowserThread::PostDelayedTask(
+        BrowserThread::UI, FROM_HERE,
+        base::Bind(DoCheckForUpdate, cus, pnacl),
+        base::TimeDelta::FromSeconds(kInitialDelaySeconds));
+  }
 }
 
 // Check if there is an existing version on disk first to know when