Make --show-app-list go to the chrome://apps page.

chrome/browser/ui/app_list/app_list_service_disabled.cc

Index: chrome/browser/ui/app_list/app_list_service_disabled.cc
diff --git a/chrome/browser/ui/app_list/app_list_service_disabled.cc b/chrome/browser/ui/app_list/app_list_service_disabled.cc
index a54dd7e9a21631abb7fb0b4c6714e0ac89cb5be9..676c71928cd5d4ac1582598965661769a5bbc749 100644
--- a/chrome/browser/ui/app_list/app_list_service_disabled.cc
+++ b/chrome/browser/ui/app_list/app_list_service_disabled.cc
@@ -6,6 +6,12 @@
 #include "base/macros.h"
 #include "base/memory/singleton.h"
 #include "chrome/browser/ui/app_list/app_list_service.h"
+#include "chrome/browser/ui/browser.h"

[tapted, 2016/05/18 03:58:27]

bleh all this should be #if defined(TOOLKIT_VIEWS) too -  I think that's the
most robust way. Currently android gets

../../chrome/browser/ui/app_list/app_list_service_disabled.cc:27:error:
undefined reference to 'chrome::FindLastActive()'
../../chrome/browser/ui/app_list/app_list_service_disabled.cc:32:error:
undefined reference to 'chrome::Navigate(chrome::NavigateParams*)'

+#include "chrome/browser/ui/browser_finder.h"
+#include "chrome/browser/ui/browser_navigator.h"
+#include "chrome/browser/ui/browser_navigator_params.h"
+#include "chrome/common/chrome_switches.h"
+#include "ui/base/page_transition_types.h"

[tapted, 2016/05/18 03:17:04]

looks like you also need

#include "base/command_line.h"
#include "chrome/common/url_constants.h"

 
 namespace {
 
@@ -75,5 +81,14 @@ void AppListService::RegisterPrefs(PrefRegistrySimple* registry) {}
 bool AppListService::HandleLaunchCommandLine(
     const base::CommandLine& command_line,
     Profile* launch_profile) {
-  return false;
+  if (!command_line.HasSwitch(switches::kShowAppList))
+    return false;
+
+  Browser* browser = chrome::FindLastActive();
+
+  chrome::NavigateParams params(browser ? browser->profile() : launch_profile,
+                                GURL(chrome::kChromeUIAppsURL),
+                                ui::PAGE_TRANSITION_AUTO_BOOKMARK);
+  chrome::Navigate(&params);
+  return true;
 }