[iOS CBCM] Add command-line switch to enable CBCM on iOS

In preparation for bringing Chrome Browser Cloud Management to iOS, this
adds a command-line switch to control whether CBCM is enabled. It needs
to be a command-line flag because policy infrastructure is initialized
before Finch / about flags and field trials.

Bug: 1066495
Change-Id: I0bd27e5ee863deda949afa64b248ca5445f9ef8e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2316620
Commit-Queue: Guillaume Jenkins <gujen@google.com>
Reviewed-by: Rohit Rao <rohitrao@chromium.org>
Cr-Commit-Position: refs/heads/master@{#791912}

ios/chrome/browser/chrome_switches.cc

@@ -24,6 +24,10 @@ const char kDisableIOSPasswordSuggestions[] =
 const char kDisableThirdPartyKeyboardWorkaround[] =
     "disable-third-party-keyboard-workaround";
 
+// Enables Chrome Browser Cloud Management flow.
+const char kEnableChromeBrowserCloudManagement[] =
+    "enable-chrome-browser-cloud-management";
+
 // Enables enterprise policy support.
 const char kEnableEnterprisePolicy[] = "enable-enterprise-policy";
 

ios/chrome/browser/chrome_switches.h

@@ -13,6 +13,7 @@ extern const char kDisableEnterprisePolicy[];
 extern const char kDisableIOSPasswordSuggestions[];
 extern const char kDisableThirdPartyKeyboardWorkaround[];
 
+extern const char kEnableChromeBrowserCloudManagement[];
 extern const char kEnableEnterprisePolicy[];
 extern const char kEnableIOSHandoffToOtherDevices[];
 extern const char kEnableSpotlightActions[];

ios/chrome/browser/policy/policy_features.cc

@@ -4,6 +4,8 @@
 
 #include "ios/chrome/browser/policy/policy_features.h"
 
+#include <string>
+
 #include "base/command_line.h"
 #include "components/version_info/version_info.h"
 #include "ios/chrome/browser/chrome_switches.h"
@@ -21,18 +23,27 @@ const base::Feature kURLBlocklistIOS{"URLBlocklistIOS",
 
 namespace {
 
+bool HasSwitch(const std::string& switch_name) {
+  // Most policy features must be controlled via the command line because policy
+  // infrastructure must be initialized before about:flags or field trials.
+  // Using a command line flag is the only way to control these features at
+  // runtime.
+  base::CommandLine* command_line = base::CommandLine::ForCurrentProcess();
+  return command_line->HasSwitch(switch_name);
+}
+
 // Returns true if the current command line contains the
 // |kDisableEnterprisePolicy| switch.
 bool IsDisableEnterprisePolicySwitchPresent() {
-  // This feature is controlled via the command line because policy must be
-  // initialized before about:flags or field trials. Using a command line flag
-  // is the only way to control this feature at runtime.
-  base::CommandLine* command_line = base::CommandLine::ForCurrentProcess();
-  return command_line->HasSwitch(switches::kDisableEnterprisePolicy);
+  return HasSwitch(switches::kDisableEnterprisePolicy);
 }
 
 }  // namespace
 
+bool IsChromeBrowserCloudManagementEnabled() {
+  return HasSwitch(switches::kEnableChromeBrowserCloudManagement);
+}
+
 bool IsEditBookmarksIOSEnabled() {
   return base::FeatureList::IsEnabled(kEditBookmarksIOS);
 }
@@ -46,11 +57,7 @@ bool ShouldInstallEnterprisePolicyHandlers() {
 }
 
 bool ShouldInstallManagedBookmarksPolicyHandler() {
-  // This feature is controlled via the command line because policy must be
-  // initialized before about:flags or field trials. Using a command line flag
-  // is the only way to control this feature at runtime.
-  base::CommandLine* command_line = base::CommandLine::ForCurrentProcess();
-  return command_line->HasSwitch(switches::kInstallManagedBookmarksHandler);
+  return HasSwitch(switches::kInstallManagedBookmarksHandler);
 }
 
 bool IsManagedBookmarksEnabled() {
@@ -59,11 +66,7 @@ bool IsManagedBookmarksEnabled() {
 }
 
 bool ShouldInstallURLBlocklistPolicyHandlers() {
-  // This feature is controlled via the command line because policy must be
-  // initialized before about:flags or field trials. Using a command line flag
-  // is the only way to control this feature at runtime.
-  base::CommandLine* command_line = base::CommandLine::ForCurrentProcess();
-  return command_line->HasSwitch(switches::kInstallURLBlocklistHandlers);
+  return HasSwitch(switches::kInstallURLBlocklistHandlers);
 }
 
 bool IsURLBlocklistEnabled() {

ios/chrome/browser/policy/policy_features.h

@@ -15,6 +15,9 @@ extern const base::Feature kManagedBookmarksIOS;
 // Feature flag for supporting the URLBlocklist enterprise policy on iOS.
 extern const base::Feature kURLBlocklistIOS;
 
+// Returns true if the Chrome Browser Cloud Management flow is enabled.
+bool IsChromeBrowserCloudManagementEnabled();
+
 // Returns true if EditBookmarksEnabled enterprise policy is supported on iOS.
 bool IsEditBookmarksIOSEnabled();