[AST/TypeChecker] Remove DynamicLookup flag.

We detect whether we’re performing AnyObject lookup based on 
whether we are looking into AnyObject; these two DynamicLookup
flags are unused.

Author: DougGregor

include/swift/AST/LookupKinds.h

@@ -37,29 +37,25 @@ enum NLOptions : unsigned {
   /// Remove overridden declarations from the set of results.
   NL_RemoveOverridden = 0x08,
 
-  /// For existentials involving the special \c AnyObject protocol,
-  /// allow lookups to find members of all classes.
-  NL_DynamicLookup = 0x10,
-
   /// Don't check access when doing lookup into a type.
   ///
   /// This option is not valid when performing lookup into a module.
-  NL_IgnoreAccessControl = 0x20,
+  NL_IgnoreAccessControl = 0x10,
 
   /// This lookup is known to be a non-cascading dependency, i.e. one that does
   /// not affect downstream files.
   ///
   /// \see NL_KnownDependencyMask
-  NL_KnownNonCascadingDependency = 0x40,
+  NL_KnownNonCascadingDependency = 0x20,
 
   /// This lookup is known to be a cascading dependency, i.e. one that can
   /// affect downstream files.
   ///
   /// \see NL_KnownDependencyMask
-  NL_KnownCascadingDependency = 0x80,
+  NL_KnownCascadingDependency = 0x40,
 
   /// This lookup should only return type declarations.
-  NL_OnlyTypes = 0x100,
+  NL_OnlyTypes = 0x80,
 
   /// This lookup is known to not add any additional dependencies to the
   /// primary source file.

lib/Sema/TypeCheckDeclOverride.cpp

@@ -627,10 +627,6 @@ SmallVector<OverrideMatch, 2> OverrideMatcher::match(
   if (members.empty() || name != membersName) {
     auto lookupOptions = defaultMemberLookupOptions;
 
-    // Class methods cannot override declarations only
-    // visible via dynamic dispatch.
-    lookupOptions -= NameLookupFlags::DynamicLookup;
-
     // Class methods cannot override declarations only
     // visible as protocol requirements or protocol
     // extension members.

lib/Sema/TypeCheckNameLookup.cpp

@@ -370,8 +370,6 @@ LookupResult TypeChecker::lookupMember(DeclContext *dc,
   NLOptions subOptions = NL_QualifiedDefault;
   if (options.contains(NameLookupFlags::KnownPrivate))
     subOptions |= NL_KnownNonCascadingDependency;
-  if (options.contains(NameLookupFlags::DynamicLookup))
-    subOptions |= NL_DynamicLookup;
   if (options.contains(NameLookupFlags::IgnoreAccessControl))
     subOptions |= NL_IgnoreAccessControl;
 

lib/Sema/TypeCheckPattern.cpp

@@ -132,8 +132,7 @@ lookupEnumMemberElement(TypeChecker &TC, DeclContext *DC, Type ty,
 
   // Look up the case inside the enum.
   // FIXME: We should be able to tell if this is a private lookup.
-  NameLookupOptions lookupOptions
-    = defaultMemberLookupOptions - NameLookupFlags::DynamicLookup;
+  NameLookupOptions lookupOptions = defaultMemberLookupOptions;
   LookupResult foundElements = TC.lookupMember(DC, ty, name, lookupOptions);
   return filterForEnumElement(TC, DC, UseLoc,
                               /*unqualifiedLookup=*/false, foundElements);

lib/Sema/TypeChecker.h

@@ -309,8 +309,7 @@ inline NameLookupOptions operator|(NameLookupFlags flag1,
 
 /// Default options for member name lookup.
 const NameLookupOptions defaultMemberLookupOptions
-  = NameLookupFlags::DynamicLookup |
-    NameLookupFlags::ProtocolMembers |
+  = NameLookupFlags::ProtocolMembers |
     NameLookupFlags::PerformConformanceCheck;
 
 /// Default options for constructor lookup.