Add support for "data" properties

src/Compilers/CSharp/Portable/CSharpExtensions.cs

@@ -1373,6 +1373,15 @@ public static Conversion ClassifyConversion(this SemanticModel? semanticModel, i
             return csmodel?.GetDeclaredSymbol(declarationSyntax, cancellationToken);
         }
 
+        /// <summary>
+        /// Given a syntax node that declares a data property, get the corresponding declared symbol.
+        /// </summary>
+        public static IPropertySymbol? GetDeclaredSymbol(this SemanticModel? semanticModel, DataPropertyDeclarationSyntax declarationSyntax, CancellationToken cancellationToken = default(CancellationToken))
+        {
+            var csmodel = semanticModel as CSharpSemanticModel;
+            return csmodel?.GetDeclaredSymbol(declarationSyntax, cancellationToken);
+        }
+
         /// <summary>
         /// Given a syntax node that declares an indexer, get the corresponding declared symbol.
         /// </summary>

src/Compilers/CSharp/Portable/CSharpResources.resx

@@ -1,17 +1,17 @@
 <?xml version="1.0" encoding="utf-8"?>
 <root>
-  <!-- 
-    Microsoft ResX Schema 
-    
+  <!--
+    Microsoft ResX Schema
+
     Version 2.0
-    
-    The primary goals of this format is to allow a simple XML format 
-    that is mostly human readable. The generation and parsing of the 
-    various data types are done through the TypeConverter classes 
+
+    The primary goals of this format is to allow a simple XML format
+    that is mostly human readable. The generation and parsing of the
+    various data types are done through the TypeConverter classes
     associated with the data types.
-    
+
     Example:
-    
+
     ... ado.net/XML headers & schema ...
     <resheader name="resmimetype">text/microsoft-resx</resheader>
     <resheader name="version">2.0</resheader>
@@ -26,36 +26,36 @@
         <value>[base64 mime encoded string representing a byte array form of the .NET Framework object]</value>
         <comment>This is a comment</comment>
     </data>
-                
-    There are any number of "resheader" rows that contain simple 
+
+    There are any number of "resheader" rows that contain simple
     name/value pairs.
-    
-    Each data row contains a name, and value. The row also contains a 
-    type or mimetype. Type corresponds to a .NET class that support 
-    text/value conversion through the TypeConverter architecture. 
-    Classes that don't support this are serialized and stored with the 
+
+    Each data row contains a name, and value. The row also contains a
+    type or mimetype. Type corresponds to a .NET class that support
+    text/value conversion through the TypeConverter architecture.
+    Classes that don't support this are serialized and stored with the
     mimetype set.
-    
-    The mimetype is used for serialized objects, and tells the 
-    ResXResourceReader how to depersist the object. This is currently not 
+
+    The mimetype is used for serialized objects, and tells the
+    ResXResourceReader how to depersist the object. This is currently not
     extensible. For a given mimetype the value must be set accordingly:
-    
-    Note - application/x-microsoft.net.object.binary.base64 is the format 
-    that the ResXResourceWriter will generate, however the reader can 
+
+    Note - application/x-microsoft.net.object.binary.base64 is the format
+    that the ResXResourceWriter will generate, however the reader can
     read any of the formats listed below.
-    
+
     mimetype: application/x-microsoft.net.object.binary.base64
-    value   : The object must be serialized with 
+    value   : The object must be serialized with
             : System.Runtime.Serialization.Formatters.Binary.BinaryFormatter
             : and then encoded with base64 encoding.
-    
+
     mimetype: application/x-microsoft.net.object.soap.base64
-    value   : The object must be serialized with 
+    value   : The object must be serialized with
             : System.Runtime.Serialization.Formatters.Soap.SoapFormatter
             : and then encoded with base64 encoding.
 
     mimetype: application/x-microsoft.net.object.bytearray.base64
-    value   : The object must be serialized into a byte array 
+    value   : The object must be serialized into a byte array
             : using a System.ComponentModel.TypeConverter
             : and then encoded with base64 encoding.
     -->
@@ -4612,7 +4612,7 @@ To remove the warning, you can use /reference instead (set the Embed Interop Typ
 -instrument:TestCoverage      Produce an assembly instrumented to collect
                               coverage information
 -sourcelink:&lt;file&gt;            Source link info to embed into PDB.
- 
+
                        - ERRORS AND WARNINGS -
 -warnaserror[+|-]             Report all warnings as errors
 -warnaserror[+|-]:&lt;warn list&gt; Report specific warnings as errors
@@ -6280,4 +6280,7 @@ To remove the warning, you can use /reference instead (set the Embed Interop Typ
   <data name="ERR_DoesNotOverrideMethodFromObject" xml:space="preserve">
     <value>'{0}' does not override the method from 'object'.</value>
   </data>
+  <data name="IDS_FeatureDataProperties" xml:space="preserve">
+    <value>data properties</value>
+  </data>
 </root>