Add share_target field to Manifest.

content/renderer/manifest/manifest_parser.h

Index: content/renderer/manifest/manifest_parser.h
diff --git a/content/renderer/manifest/manifest_parser.h b/content/renderer/manifest/manifest_parser.h
index 610566b4b8ddfe4ec1b52d93cb894cb11be38af2..ad7ca654fb4935ea89f4204281c91ab15c30ea50 100644
--- a/content/renderer/manifest/manifest_parser.h
+++ b/content/renderer/manifest/manifest_parser.h
@@ -146,6 +146,20 @@ class CONTENT_EXPORT ManifestParser {
   std::vector<Manifest::Icon> ParseIcons(
       const base::DictionaryValue& dictionary);
 
+  // Parses the 'url_template' field of a Share Target, as defined in:
+  // https://github.com/WICG/web-share-target/blob/master/docs/interface.md
+  // Returns the parsed string if any, or a null string if the field was not
+  // present, or didn't contain a string.
+  base::NullableString16 ParseShareTargetURLTemplate(
+      const base::DictionaryValue& share_target);
+
+  // Parses the 'share_target' field of a Manifest, as defined in:
+  // https://github.com/WICG/web-share-target/blob/master/docs/interface.md
+  // Returns the parsed Web Share target. The returned Share Target is null if
+  // the field didn't exist, parsing failed, or it was empty.
+  Manifest::ShareTarget ParseShareTarget(
+      const base::DictionaryValue& dictionary);
+
   // Parses the 'platform' field of a related application, as defined in:
   // https://w3c.github.io/manifest/#dfn-steps-for-processing-the-platform-member-of-an-application
   // Returns the parsed string if any, a null string if the parsing failed.