WebApps: Fixes a crash upon sign in in Chrome OS.

This was caused because PendingAppManager's shortcut_manager_ was not
being initialized in SetSubsystems. It was not caught by existing tests
because we disable shortcut creation in tests, as it's hard to
clean up afterwards.

In a followup CL I'm going to try and push shortcuts being disabled
further down the stack.

Bug: 1019319
Change-Id: I91d8b22eb5cdba67a23481db778e0c4f9724e632
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1890394Reviewed-by: Giovanni Ortuño Urquidi <ortuno@chromium.org>
Commit-Queue: Jay Harris <harrisjay@chromium.org>
Cr-Commit-Position: refs/heads/master@{#711611}

chrome/browser/web_applications/components/pending_app_manager.cc

@@ -37,9 +37,11 @@ PendingAppManager::~PendingAppManager() {
 }
 
 void PendingAppManager::SetSubsystems(AppRegistrar* registrar,
+                                      AppShortcutManager* shortcut_manager,
                                       WebAppUiManager* ui_manager,
                                       InstallFinalizer* finalizer) {
   registrar_ = registrar;
+  shortcut_manager_ = shortcut_manager;
   ui_manager_ = ui_manager;
   finalizer_ = finalizer;
 }

chrome/browser/web_applications/components/pending_app_manager.h

@@ -56,6 +56,7 @@ class PendingAppManager {
   virtual ~PendingAppManager();
 
   void SetSubsystems(AppRegistrar* registrar,
+                     AppShortcutManager* shortcut_manager,
                      WebAppUiManager* ui_manager,
                      InstallFinalizer* finalizer);
 

chrome/browser/web_applications/test/test_pending_app_manager.cc

@@ -24,7 +24,7 @@ TestPendingAppManager::TestPendingAppManager(TestAppRegistrar* registrar)
       deduped_uninstall_count_(0),
       registrar_(registrar) {
   // TODO(crbug.com/973324): Wire this up to a TestInstallFinalizer.
-  SetSubsystems(registrar, nullptr, nullptr);
+  SetSubsystems(registrar, nullptr, nullptr, nullptr);
 }
 
 TestPendingAppManager::~TestPendingAppManager() = default;

chrome/browser/web_applications/web_app_provider.cc

@@ -218,7 +218,8 @@ void WebAppProvider::ConnectSubsystems() {
                                   install_finalizer_.get());
   manifest_update_manager_->SetSubsystems(registrar_.get(), ui_manager_.get(),
                                           install_manager_.get());
-  pending_app_manager_->SetSubsystems(registrar_.get(), ui_manager_.get(),
+  pending_app_manager_->SetSubsystems(registrar_.get(), shortcut_manager_.get(),
+                                      ui_manager_.get(),
                                       install_finalizer_.get());
   external_web_app_manager_->SetSubsystems(pending_app_manager_.get());
   system_web_app_manager_->SetSubsystems(pending_app_manager_.get(),