[Sema] -serialize-diagnostics-path should imply -diagnostics-editor-mode so that live issues and editor builds can have the consistent behavior. (swiftlang#9166)

Author: nkcsgexi

lib/Frontend/CompilerInvocation.cpp

@@ -902,7 +902,8 @@ static bool ParseLangArgs(LangOptions &Opts, ArgList &Args,
 
   Opts.UseMalloc |= Args.hasArg(OPT_use_malloc);
 
-  Opts.DiagnosticsEditorMode |= Args.hasArg(OPT_diagnostics_editor_mode);
+  Opts.DiagnosticsEditorMode |= Args.hasArg(OPT_diagnostics_editor_mode,
+                                            OPT_serialize_diagnostics_path);
 
   Opts.EnableExperimentalPropertyBehaviors |=
     Args.hasArg(OPT_enable_experimental_property_behaviors);

test/decl/protocol/conforms/fixit_stub_editor_implied.swift

@@ -0,0 +1,13 @@
+// RUN: %target-typecheck-verify-swift -serialize-diagnostics-path %t.diag
+
+protocol P1 {
+  func foo1()
+  func foo2()
+}
+
+protocol P2 {
+  func bar1()
+  func bar2()
+}
+
+class C1 : P1, P2 {} // expected-error{{type 'C1' does not conform to protocol 'P1'}} expected-error{{type 'C1' does not conform to protocol 'P2'}} expected-note{{do you want to add protocol stubs?}}{{20-20=\n    func foo1() {\n        <#code#>\n    \}\n\n    func foo2() {\n        <#code#>\n    \}\n\n    func bar1() {\n        <#code#>\n    \}\n\n    func bar2() {\n        <#code#>\n    \}\n}}