Add 'throw' keyword ot the completion list in certain contexts.

src/EditorFeatures/CSharpTest2/Recommendations/ThrowKeywordRecommenderTests.cs

@@ -143,5 +143,55 @@ public async Task TestInNestedIf()
     if (caseOrDefaultKeyword.Kind != SyntaxKind.CaseKeyword && caseOrDefaultKeyword.Kind != SyntaxKind.DefaultKeyword) 
       $$"));
         }
+
+        [WorkItem(9099, "https://github.com/dotnet/roslyn/issues/9099")]
+        [Fact, Trait(Traits.Feature, Traits.Features.KeywordRecommending)]
+        public async Task TestAfterArrow()
+        {
+            await VerifyKeywordAsync(
+@"class C
+{
+    void Foo() => $$
+");
+        }
+
+        [WorkItem(9099, "https://github.com/dotnet/roslyn/issues/9099")]
+        [Fact, Trait(Traits.Feature, Traits.Features.KeywordRecommending)]
+        public async Task TestAfterQuestionQuestion()
+        {
+            await VerifyKeywordAsync(
+@"class C
+{
+    public C(object o)
+    {
+        _o = o ?? $$
+");
+        }
+
+        [WorkItem(9099, "https://github.com/dotnet/roslyn/issues/9099")]
+        [Fact, Trait(Traits.Feature, Traits.Features.KeywordRecommending)]
+        public async Task TestInConditional1()
+        {
+            await VerifyKeywordAsync(
+@"class C
+{
+    public C(object o)
+    {
+        var v= true ? $$
+");
+        }
+
+        [WorkItem(9099, "https://github.com/dotnet/roslyn/issues/9099")]
+        [Fact, Trait(Traits.Feature, Traits.Features.KeywordRecommending)]
+        public async Task TestInConditional2()
+        {
+            await VerifyKeywordAsync(
+@"class C
+{
+    public C(object o)
+    {
+        var v= true ? 0 : $$
+");
+        }
     }
 }

src/Features/CSharp/Portable/Completion/KeywordRecommenders/ThrowKeywordRecommender.cs

@@ -14,9 +14,32 @@ public ThrowKeywordRecommender()
 
         protected override bool IsValidContext(int position, CSharpSyntaxContext context, CancellationToken cancellationToken)
         {
-            return
-                context.IsStatementContext ||
-                context.IsGlobalStatementContext;
+            if (context.IsStatementContext || context.IsGlobalStatementContext)
+            {
+                return true;
+            }
+
+            // void M() => throw
+            if (context.TargetToken.Kind() == SyntaxKind.EqualsGreaterThanToken)
+            {
+                return true;
+            }
+
+            // val ?? throw
+            if (context.TargetToken.Kind() == SyntaxKind.QuestionQuestionToken)
+            {
+                return true;
+            }
+
+            //  expr ? throw : ...
+            //  expr ? ... : throw
+            if (context.TargetToken.Kind() == SyntaxKind.QuestionToken ||
+                context.TargetToken.Kind() == SyntaxKind.ColonToken)
+            {
+                return context.TargetToken.Parent.Kind() == SyntaxKind.ConditionalExpression;
+            }
+
+            return false;
         }
     }
-}
+}
\ No newline at end of file

src/Workspaces/CSharp/Portable/Extensions/ContextQuery/SyntaxTokenExtensions.cs

@@ -513,12 +513,7 @@ public static bool IsAfterYieldKeyword(this SyntaxToken targetToken)
             // yield |
             // yield r|
 
-            if (targetToken.IsKindOrHasMatchingText(SyntaxKind.YieldKeyword))
-            {
-                return true;
-            }
-
-            return false;
+            return targetToken.IsKindOrHasMatchingText(SyntaxKind.YieldKeyword);
         }
 
         public static bool IsAnyAccessorDeclarationContext(this SyntaxToken targetToken, int position, SyntaxKind kind = SyntaxKind.None)