Expose Physical Web metadata to native clients over JNI

components/physical_web/data_source/physical_web_data_source.h

Index: components/physical_web/data_source/physical_web_data_source.h
diff --git a/components/physical_web/data_source/physical_web_data_source.h b/components/physical_web/data_source/physical_web_data_source.h
index 6225b7aab9953d5fdae8ea61d4c5b3474b777781..927e8933cc979c49c9d690f6b3525bbd34287d44 100644
--- a/components/physical_web/data_source/physical_web_data_source.h
+++ b/components/physical_web/data_source/physical_web_data_source.h
@@ -13,6 +13,16 @@ class ListValue;
 
 class PhysicalWebListener;
 
+// Dictionary keys for reading Physical Web URL metadata.
+extern const char kPhysicalWebDescriptionKey[];
+extern const char kPhysicalWebDistanceEstimateKey[];
+extern const char kPhysicalWebGroupIdKey[];
+extern const char kPhysicalWebIconUrlKey[];
+extern const char kPhysicalWebResolvedUrlKey[];
+extern const char kPhysicalWebScanTimestampKey[];
+extern const char kPhysicalWebScannedUrlKey[];
+extern const char kPhysicalWebTitleKey[];
+
 // Helper class for accessing Physical Web metadata and controlling the scanner.
 class PhysicalWebDataSource {
  public: