cros: Add switch to customize rlz ping delay

To use the switch:
1) Install the build that contains this CL.
2) Go to dev console, open /etc/chrome_dev.conf
3) Append:
   --rlz-ping-delay=1 (or any value)
4) Save and exit, run "restart ui" (or reboot the device) to make the
   switch take effect.

TBR=rogerta@chromium.org

Bug: None
Change-Id: I8431d0cb3a376b5e5aa0b35ff7d155110324716a
Reviewed-on: https://chromium-review.googlesource.com/994141Reviewed-by: Wenzhao (Colin) Zang <wzang@chromium.org>
Commit-Queue: Wenzhao (Colin) Zang <wzang@chromium.org>
Cr-Commit-Position: refs/heads/master@{#547938}

chrome/browser/rlz/chrome_rlz_tracker_delegate.cc

@@ -36,6 +36,11 @@
 #include "chrome/installer/util/google_update_settings.h"
 #endif
 
+#if defined(OS_CHROMEOS)
+#include "base/command_line.h"
+#include "chromeos/chromeos_switches.h"
+#endif
+
 ChromeRLZTrackerDelegate::ChromeRLZTrackerDelegate() {}
 
 ChromeRLZTrackerDelegate::~ChromeRLZTrackerDelegate() {}
@@ -44,11 +49,23 @@ ChromeRLZTrackerDelegate::~ChromeRLZTrackerDelegate() {}
 void ChromeRLZTrackerDelegate::RegisterProfilePrefs(
     user_prefs::PrefRegistrySyncable* registry) {
 #if BUILDFLAG(ENABLE_RLZ)
+  int rlz_ping_delay_seconds = 90;
 #if defined(OS_CHROMEOS)
-  registry->RegisterIntegerPref(prefs::kRlzPingDelaySeconds, 24 * 3600);
-#else
-  registry->RegisterIntegerPref(prefs::kRlzPingDelaySeconds, 90);
+  if (base::CommandLine::ForCurrentProcess()->HasSwitch(
+          chromeos::switches::kRlzPingDelay)) {
+    // Use a switch for overwriting the default delay because it doesn't seem
+    // possible to manually override the Preferences file on Chrome OS: the file
+    // is already loaded into memory by the time you modify it and any changes
+    // made get overwritten by Chrome.
+    rlz_ping_delay_seconds =
+        std::stoi(base::CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
+            chromeos::switches::kRlzPingDelay));
+  } else {
+    rlz_ping_delay_seconds = 24 * 3600;
+  }
 #endif
+  registry->RegisterIntegerPref(prefs::kRlzPingDelaySeconds,
+                                rlz_ping_delay_seconds);
 #endif
 }
 

chromeos/chromeos_switches.cc

@@ -512,6 +512,9 @@ const char kOobeTimerInterval[] = "oobe-timer-interval";
 // must succeed, otherwise session restart should fail).
 const char kProfileRequiresPolicy[] = "profile-requires-policy";
 
+// The rlz ping delay (in seconds) that overwrites the default value.
+const char kRlzPingDelay[] = "rlz-ping-delay";
+
 // Overrides network stub behavior. By default, ethernet, wifi and vpn are
 // enabled, and transitions occur instantaneously. Multiple options can be
 // comma separated (no spaces). Note: all options are in the format 'foo=x'.

chromeos/chromeos_switches.h

@@ -145,6 +145,7 @@ CHROMEOS_EXPORT extern const char kOobeSkipPostLogin[];
 CHROMEOS_EXPORT extern const char kOobeSkipToLogin[];
 CHROMEOS_EXPORT extern const char kOobeTimerInterval[];
 CHROMEOS_EXPORT extern const char kProfileRequiresPolicy[];
+CHROMEOS_EXPORT extern const char kRlzPingDelay[];
 CHROMEOS_EXPORT extern const char kShillStub[];
 CHROMEOS_EXPORT extern const char kShowLoginDevOverlay[];
 CHROMEOS_EXPORT extern const char kSmsTestMessages[];