[Safe Browsing] Only check main frame and iframe URLs on Mobile, for speed.

chrome/browser/safe_browsing/remote_database_manager.cc

Index: chrome/browser/safe_browsing/remote_database_manager.cc
diff --git a/chrome/browser/safe_browsing/remote_database_manager.cc b/chrome/browser/safe_browsing/remote_database_manager.cc
index e789f44b69f1ac6fe297d155c236edc8415dcbe8..111a672097a3845d1e8ab36efa0ef35b700c0690 100644
--- a/chrome/browser/safe_browsing/remote_database_manager.cc
+++ b/chrome/browser/safe_browsing/remote_database_manager.cc
@@ -7,12 +7,25 @@
 #include <vector>
 
 #include "base/metrics/histogram_macros.h"
+#include "base/strings/string_number_conversions.h"
+#include "base/strings/string_split.h"
 #include "base/timer/elapsed_timer.h"
 #include "chrome/browser/safe_browsing/safe_browsing_api_handler.h"
+#include "components/variations/variations_associated_data.h"
 #include "content/public/browser/browser_thread.h"
 
 using content::BrowserThread;
 
+namespace {
+
+// Android field trial
+const char kAndroidFieldExperiment[] = "SafeBrowsingAndroid";
+const char kAndroidFieldParam[] = "enabled";
+const char kAndroidFieldParamEnabledValue[] = "true";
+const char kAndroidTypesToCheckParam[] = "types_to_check";
+
+}  // namespace
+
 //
 // RemoteSafeBrowsingDatabaseManager::ClientRequest methods
 //
@@ -76,10 +89,32 @@ void RemoteSafeBrowsingDatabaseManager::ClientRequest::OnRequestDone(
 // RemoteSafeBrowsingDatabaseManager methods
 //
 
-// TODO(nparker): Add tests for this class
+// TODO(nparker): Add more tests for this class
 RemoteSafeBrowsingDatabaseManager::RemoteSafeBrowsingDatabaseManager()
     : enabled_(false) {
-  DCHECK_CURRENTLY_ON(BrowserThread::UI);
+
+  // Check if the field trial is enabled.
+  const std::string enabled_param = variations::GetVariationParamValue(
+      kAndroidFieldExperiment, kAndroidFieldParam);
+  is_android_field_trial_enabled_ =
+      (enabled_param == kAndroidFieldParamEnabledValue);
+
+  // Decide which resource types to check. These two are the minimum.
+  resource_types_to_check_.insert(content::RESOURCE_TYPE_MAIN_FRAME);
+  resource_types_to_check_.insert(content::RESOURCE_TYPE_SUB_FRAME);
+
+  // The param is expected to be a comma-separated list of ints
+  // corresponding to the enum types.
+  const std::string ints_str = variations::GetVariationParamValue(
+      kAndroidFieldExperiment, kAndroidTypesToCheckParam);
+  for (const std::string& val_str : base::SplitString(
+           ints_str, ",", base::TRIM_WHITESPACE, base::SPLIT_WANT_ALL)) {
+    int i;
+    if (base::StringToInt(val_str, &i) && i >= 0 &&
+        i < content::RESOURCE_TYPE_LAST_TYPE) {
+      resource_types_to_check_.insert(static_cast<content::ResourceType>(i));
+    }
+  }
 }
 
 RemoteSafeBrowsingDatabaseManager::~RemoteSafeBrowsingDatabaseManager() {
@@ -87,7 +122,17 @@ RemoteSafeBrowsingDatabaseManager::~RemoteSafeBrowsingDatabaseManager() {
 }
 
 bool RemoteSafeBrowsingDatabaseManager::IsSupported() const {
-  return SafeBrowsingApiHandler::GetInstance() != nullptr;
+  return SafeBrowsingApiHandler::GetInstance() != nullptr &&
+         is_android_field_trial_enabled_;
+}
+
+bool RemoteSafeBrowsingDatabaseManager::ChecksAreAlwaysAsync() const {
+  return true;
+}
+
+bool RemoteSafeBrowsingDatabaseManager::CanCheckResourceType(
+    content::ResourceType resource_type) const {
+  return resource_types_to_check_.count(resource_type) > 0;
 }
 
 bool RemoteSafeBrowsingDatabaseManager::CanCheckUrl(const GURL& url) const {
@@ -218,4 +263,3 @@ void RemoteSafeBrowsingDatabaseManager::StopOnIOThread(bool shutdown) {
   }
   enabled_ = false;
 }
-