put both partial method symbol to event queue.

src/Compilers/CSharp/Portable/Compiler/MethodCompiler.cs

@@ -1030,8 +1030,7 @@ public override object VisitField(FieldSymbol symbol, TypeCompilationState argum
                         return semanticModel;
                     });
 
-                    MethodSymbol symbolToProduce = methodSymbol.PartialDefinitionPart ?? methodSymbol;
-                    _compilation.EventQueue.TryEnqueue(new SymbolDeclaredCompilationEvent(_compilation, symbolToProduce, lazySemanticModel));
+                    _compilation.EventQueue.TryEnqueue(new SymbolDeclaredCompilationEvent(_compilation, methodSymbol, lazySemanticModel));
                 }
 
                 // Don't lower if we're not emitting or if there were errors. 

src/Compilers/CSharp/Test/Semantic/Diagnostics/GetDiagnosticsTests.cs

@@ -271,9 +271,10 @@ private static bool DequeueCompilationEvents(AsyncQueue<CompilationEvent> eventQ
                     {
                         var symbol = symbolDeclaredEvent.Symbol;
                         var added = declaredSymbolNames.Add(symbol.Name);
-                        Assert.True(added, "Unexpected multiple symbol declared events for symbol " + symbol);
-                        var method = symbol as Symbols.MethodSymbol;
-                        Assert.Null(method?.PartialDefinitionPart); // we should never get a partial method's implementation part
+                        if (!added)
+                        {
+                            Assert.True(((Symbols.SourceMemberMethodSymbol)symbol).IsPartial, "Unexpected multiple symbol declared events for symbol " + symbol);
+                        }
                     }
                     else
                     {
@@ -293,7 +294,7 @@ private static bool DequeueCompilationEvents(AsyncQueue<CompilationEvent> eventQ
         public void TestEventQueueCompletionForEmptyCompilation()
         {
             var compilation = CreateCompilationWithMscorlib45(SpecializedCollections.EmptyEnumerable<SyntaxTree>()).WithEventQueue(new AsyncQueue<CompilationEvent>());
-            
+
             // Force complete compilation event queue
             var unused = compilation.GetDiagnostics();
 

src/Compilers/VisualBasic/Portable/Compilation/MethodCompiler.vb

@@ -1222,8 +1222,7 @@ Namespace Microsoft.CodeAnalysis.VisualBasic
                                 End If
                                 Return semanticModel
                             End Function)
-                        Dim symbolToProduce = If(method.PartialDefinitionPart, method)
-                        compilation.EventQueue.TryEnqueue(New SymbolDeclaredCompilationEvent(compilation, symbolToProduce, lazySemanticModel))
+                        compilation.EventQueue.TryEnqueue(New SymbolDeclaredCompilationEvent(compilation, method, lazySemanticModel))
                     End If
                 End If
             End If

src/Compilers/VisualBasic/Test/Semantic/Diagnostics/GetDiagnosticsTests.vb

 ' Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
 
-Imports System.Xml.Linq
 Imports Microsoft.CodeAnalysis.Diagnostics
 Imports Microsoft.CodeAnalysis.Test.Utilities
 Imports Roslyn.Test.Utilities
@@ -424,9 +423,10 @@ BC31030: Conditional compilation constant '2' is not valid: Identifier expected.
                     Dim symbolDeclaredEvent = TryCast(compEvent, SymbolDeclaredCompilationEvent)
                     If symbolDeclaredEvent IsNot Nothing Then
                         Dim symbol = symbolDeclaredEvent.Symbol
-                        Assert.True(declaredSymbolNames.Add(symbol.Name), "Unexpected multiple symbol declared events for same symbol")
-                        Dim method = TryCast(symbol, Symbols.MethodSymbol)
-                        Assert.Null(method?.PartialDefinitionPart) ' we should never get a partial method's implementation part
+                        Dim added = declaredSymbolNames.Add(symbol.Name)
+                        If Not added Then
+                            Assert.True(DirectCast(symbol, Symbols.SourceMethodSymbol).IsPartial, "Unexpected multiple symbol declared events for same symbol " + symbol.Name)
+                        End If
                     Else
                         Dim compilationCompeletedEvent = TryCast(compEvent, CompilationUnitCompletedEvent)
                         If compilationCompeletedEvent IsNot Nothing Then