Make DETECT_IMPORTANT_CONTENT the default Plugins content setting based

components/content_settings/core/browser/DEPS

Index: components/content_settings/core/browser/DEPS
diff --git a/components/content_settings/core/browser/DEPS b/components/content_settings/core/browser/DEPS
index dcf594c9ad6801a715f4e4a11880b5b6882c78f9..92d69a64e05307e2ce7aa50e22d9552cf8eea7b4 100644
--- a/components/content_settings/core/browser/DEPS
+++ b/components/content_settings/core/browser/DEPS
@@ -1,6 +1,13 @@
 include_rules = [
+  "+components/content_settings/core/common",
   "+components/content_settings/core/test",
   "+components/pref_registry",
   "+net/base",
   "+net/cookies",
 ]
+
+specific_include_rules = {
+  '.*_[a-z]*test\.cc': [
+    '+base/test',
+  ],
+}