[Frontend] Don't enable EmbeddedRestrictions warnings under -suppress-warnings

Fixes #84697.

Author: DougGregor

lib/Frontend/CompilerInvocation.cpp

@@ -2646,7 +2646,7 @@ static bool ParseDiagnosticArgs(DiagnosticOptions &Opts, ArgList &Args,
 
   // If the "embedded" flag was provided, enable the EmbeddedRestrictions
   // warning group. This group is opt-in in non-Embedded builds.
-  if (isEmbedded(Args)) {
+  if (isEmbedded(Args) && !Args.hasArg(OPT_suppress_warnings)) {
     Opts.WarningsAsErrorsRules.push_back(
         WarningAsErrorRule(WarningAsErrorRule::Action::Disable,
                            "EmbeddedRestrictions"));

test/embedded/restrictions.swift

@@ -1,6 +1,6 @@
 // RUN: %target-typecheck-verify-swift -Wwarning EmbeddedRestrictions -verify-additional-prefix nonembedded-
 // RUN: %target-typecheck-verify-swift -enable-experimental-feature Embedded -verify-additional-prefix embedded-
-
+// RUN: %target-swift-frontend -typecheck %s -suppress-warnings -enable-experimental-feature Embedded -DSUPPRESS_WEAK
 // REQUIRES: swift_in_compiler
 // REQUIRES: swift_feature_Embedded
 
@@ -54,12 +54,14 @@ struct SomeStruct {
 public class MyClass { }
 
 public struct MyStruct {
+  #if !SUPPRESS_WEAK
   var normalVar: MyClass
   weak var weakVar: MyClass? // expected-nonembedded-warning {{attribute 'weak' cannot be used in Embedded Swift}}
   // expected-embedded-error@-1 {{attribute 'weak' cannot be used in Embedded Swift}}
 
   unowned var unownedVar: MyClass // expected-nonembedded-warning {{attribute 'unowned' cannot be used in Embedded Swift}}
   // expected-embedded-error @-1{{attribute 'unowned' cannot be used in Embedded Swift}}
+  #endif
 
   unowned(unsafe) var unownedUnsafe: MyClass
 }