Add metrics for paths in file scheme exceptions in content settings.

components/content_settings/core/common/content_settings_pattern.h

Index: components/content_settings/core/common/content_settings_pattern.h
diff --git a/components/content_settings/core/common/content_settings_pattern.h b/components/content_settings/core/common/content_settings_pattern.h
index fc7b6091f07caf7b35d29bf00adecae73e50e0e5..f0432f5993094707c41194143ce5d967766ee54d 100644
--- a/components/content_settings/core/common/content_settings_pattern.h
+++ b/components/content_settings/core/common/content_settings_pattern.h
@@ -194,6 +194,10 @@ class ContentSettingsPattern {
   // Returns scheme type of pattern.
   ContentSettingsPattern::SchemeType GetScheme() const;
 
+  // True if this pattern has a non-empty path.  Can only be used for patterns
+  // with file: schemes.
+  bool HasPath() const;
+
   // Compares the pattern with a given |other| pattern and returns the
   // |Relation| of the two patterns.
   Relation Compare(const ContentSettingsPattern& other) const;