Split content script injections into multiple tasks

extensions/common/feature_switch.h

Index: extensions/common/feature_switch.h
diff --git a/extensions/common/feature_switch.h b/extensions/common/feature_switch.h
index 6e2f8e7abad26aea46e520971f32ce80d79f2f54..390a758dd685be3c5a9aac7e8284470befb73cd2 100644
--- a/extensions/common/feature_switch.h
+++ b/extensions/common/feature_switch.h
@@ -41,6 +41,7 @@ class FeatureSwitch {
   static FeatureSwitch* trace_app_source();
   static FeatureSwitch* load_media_router_component_extension();
   static FeatureSwitch* native_crx_bindings();
+  static FeatureSwitch* yield_between_content_script_runs();
 
   enum DefaultValue {
     DEFAULT_ENABLED,
@@ -53,6 +54,12 @@ class FeatureSwitch {
     OVERRIDE_DISABLED
   };
 
+  enum CachedValue {
+    NOT_CACHED,
+    CACHED_ENABLED,
+    CACHED_DISABLED
+  };
+
   // A temporary override for the switch value.
   class ScopedOverride {
    public:
@@ -88,12 +95,14 @@ class FeatureSwitch {
  private:
   std::string GetLegacyEnableFlag() const;
   std::string GetLegacyDisableFlag() const;
+  bool ComputeValue() const;
 
   const base::CommandLine* command_line_;
   const char* switch_name_;
   const char* field_trial_name_;
   bool default_value_;
   OverrideValue override_value_;
+  mutable CachedValue cached_value_;

[Devlin, 2017/03/10 03:18:45]

nit: maybe use a base::Optional<bool> here?

[Kunihiko Sakamoto, 2017/03/10 07:07:28]

Done.

 
   DISALLOW_COPY_AND_ASSIGN(FeatureSwitch);
 };