[webnfc] NDEFScanOptions#mediaType being undefined means do not filter

And the empty string should just match on empty.

The spec change:
https://github.com/w3c/web-nfc/pull/496
https://github.com/w3c/web-nfc/pull/498

BUG=520391

Change-Id: Idae55b976a6fbbdd252f6227cbe13ee50d16269c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1986632Reviewed-by: Rijubrata Bhaumik <rijubrata.bhaumik@intel.com>
Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Commit-Queue: Leon Han <leon.han@intel.com>
Cr-Commit-Position: refs/heads/master@{#728813}

services/device/nfc/android/java/src/org/chromium/device/nfc/NfcImpl.java

@@ -612,8 +612,7 @@ public class NfcImpl implements Nfc {
                     continue;
                 }
             }
-            if (!options.mediaType.isEmpty()
-                    && !options.mediaType.equals(message.data[i].mediaType)) {
+            if (options.mediaType != null && !options.mediaType.equals(message.data[i].mediaType)) {
                 continue;
             }
 

services/device/nfc/android/junit/src/org/chromium/device/nfc/NFCTest.java

@@ -1234,7 +1234,6 @@ public class NFCTest {
 
     private NdefScanOptions createNdefScanOptions() {
         NdefScanOptions options = new NdefScanOptions();
-        options.mediaType = "";
         return options;
     }
 

services/device/public/mojom/nfc.mojom

@@ -106,11 +106,13 @@ struct NDEFScanOptions {
   // string means must match on empty.
   string? id;
 
-  // Defines record type filtering constraint.
+  // Defines record type filtering constraint. Null means don't filter, empty
+  // string means must match on empty.
   string? record_type;
 
-  // Defines media type filtering constraint. Empty string means don't filter.
-  string media_type;
+  // Defines media type filtering constraint. Null means don't filter, empty
+  // string means must match on empty.
+  string? media_type;
 };
 
 interface NFC {

third_party/blink/renderer/modules/nfc/ndef_scan_options.idl

@@ -6,6 +6,6 @@
 dictionary NDEFScanOptions {
     USVString id;
     USVString recordType;
-    USVString mediaType = "";
+    USVString mediaType;
     AbortSignal? signal;
 };

third_party/blink/renderer/modules/nfc/nfc_type_converters.cc

@@ -70,9 +70,8 @@ TypeConverter<NDEFScanOptionsPtr, const blink::NDEFScanOptions*>::Convert(
     const blink::NDEFScanOptions* scanOptions) {
   // https://w3c.github.io/web-nfc/#dom-ndefscanoptions
   // Default values for NDEFScanOptions dictionary are:
-  // id = undefined, recordType = undefined, mediaType = ""
+  // id = undefined, recordType = undefined, mediaType = undefined
   NDEFScanOptionsPtr scanOptionsPtr = NDEFScanOptions::New();
-  scanOptionsPtr->media_type = scanOptions->mediaType();
 
   if (scanOptions->hasId()) {
     scanOptionsPtr->id = scanOptions->id();
@@ -82,6 +81,10 @@ TypeConverter<NDEFScanOptionsPtr, const blink::NDEFScanOptions*>::Convert(
     scanOptionsPtr->record_type = scanOptions->recordType();
   }
 
+  if (scanOptions->hasMediaType()) {
+    scanOptionsPtr->media_type = scanOptions->mediaType();
+  }
+
   return scanOptionsPtr;
 }
 

third_party/blink/web_tests/external/wpt/resources/chromium/nfc-mock.js

@@ -133,7 +133,7 @@ function matchesWatchOptions(message, options) {
         options.recordType !== record.recordType) {
       continue;
     }
-    if (options.mediaType !== '' && options.mediaType !== record.mediaType) {
+    if (options.mediaType != null && options.mediaType !== record.mediaType) {
       continue;
     }