Fix generation of events in interfaces.

src/Compilers/CSharp/Portable/Parser/LanguageParser.cs

@@ -4083,7 +4083,7 @@ private void ParseParameterModifiers(SyntaxListBuilder modifiers)
             }
         }
 
-        private MemberDeclarationSyntax ParseEventDeclarationWithAccessors(
+        private EventDeclarationSyntax ParseEventDeclarationWithAccessors(
             SyntaxListBuilder<AttributeListSyntax> attributes,
             SyntaxListBuilder modifiers,
             SyntaxToken eventToken,
@@ -4206,7 +4206,7 @@ private void ParseParameterModifiers(SyntaxListBuilder modifiers)
             }
         }
 
-        private MemberDeclarationSyntax ParseEventFieldDeclaration(
+        private EventFieldDeclarationSyntax ParseEventFieldDeclaration(
             SyntaxListBuilder<AttributeListSyntax> attributes,
             SyntaxListBuilder modifiers,
             SyntaxToken eventToken,

src/Workspaces/CSharp/Portable/CodeGeneration/CSharpSyntaxGenerator.cs

@@ -733,18 +733,18 @@ internal override SyntaxNode AsInterfaceMember(SyntaxNode m)
                             .WithModifiers(default(SyntaxTokenList))
                             .WithAccessorList(WithoutBodies(indexer.AccessorList));
 
+                    // convert event into field event
                     case SyntaxKind.EventDeclaration:
                         var ev = (EventDeclarationSyntax)member;
-                        return ev
-                            .WithModifiers(default(SyntaxTokenList))
-                            .WithAccessorList(WithoutBodies(ev.AccessorList));
+                        return this.EventDeclaration(
+                            ev.Identifier.ValueText,
+                            ev.Type,
+                            Accessibility.NotApplicable,
+                            DeclarationModifiers.None);
 
-                    // convert event field into event
                     case SyntaxKind.EventFieldDeclaration:
                         var ef = (EventFieldDeclarationSyntax)member;
-                        this.GetAccessibilityAndModifiers(ef.Modifiers, out acc, out modifiers);
-                        var ep = this.CustomEventDeclaration(this.GetName(ef), this.ClearTrivia(this.GetType(ef)), acc, modifiers, parameters: null, addAccessorStatements: null, removeAccessorStatements: null);
-                        return this.AsInterfaceMember(ep);
+                        return ef.WithModifiers(default(SyntaxTokenList));
 
                     // convert field into property
                     case SyntaxKind.FieldDeclaration:

src/Workspaces/CSharpTest/CodeGeneration/SyntaxGeneratorTests.cs

@@ -1212,11 +1212,11 @@ public void TestInterfaceDeclarations()
 
             VerifySyntax<InterfaceDeclarationSyntax>(
                 _g.InterfaceDeclaration("i", members: new[] { _g.CustomEventDeclaration("ep", _g.IdentifierName("t"), accessibility: Accessibility.Public, modifiers: DeclarationModifiers.Static) }),
-                "interface i\r\n{\r\n    event t ep\r\n    {\r\n        add;\r\n        remove;\r\n    }\r\n}");
+                "interface i\r\n{\r\n    event t ep;\r\n}");
 
             VerifySyntax<InterfaceDeclarationSyntax>(
                 _g.InterfaceDeclaration("i", members: new[] { _g.EventDeclaration("ef", _g.IdentifierName("t"), accessibility: Accessibility.Public, modifiers: DeclarationModifiers.Static) }),
-                "interface i\r\n{\r\n    event t ef\r\n    {\r\n        add;\r\n        remove;\r\n    }\r\n}");
+                "interface i\r\n{\r\n    event t ef;\r\n}");
 
             VerifySyntax<InterfaceDeclarationSyntax>(
                 _g.InterfaceDeclaration("i", members: new[] { _g.FieldDeclaration("f", _g.IdentifierName("t"), accessibility: Accessibility.Public, modifiers: DeclarationModifiers.Sealed) }),
@@ -1677,11 +1677,7 @@ public void TestInterfaceDeclarationWithEventFromSymbol()
                 _g.Declaration(_emptyCompilation.GetTypeByMetadataName("System.ComponentModel.INotifyPropertyChanged")),
 @"public interface INotifyPropertyChanged
 {
-    event global::System.ComponentModel.PropertyChangedEventHandler PropertyChanged
-    {
-        add;
-        remove;
-    }
+    event global::System.ComponentModel.PropertyChangedEventHandler PropertyChanged;
 }");
         }
         #endregion