Remove legacy patch class syntax in VM

runtime/vm/parser.cc

Index: runtime/vm/parser.cc
diff --git a/runtime/vm/parser.cc b/runtime/vm/parser.cc
index 4617d2aaecd91d8a7506608394072f23b471f87e..8d375560576c87e3180190236686368eb01b3660 100644
--- a/runtime/vm/parser.cc
+++ b/runtime/vm/parser.cc
@@ -4634,14 +4634,6 @@ void Parser::ParseClassDeclaration(const GrowableObjectArray& pending_classes,
     is_patch = true;
     metadata_pos = TokenPosition::kNoSource;
     declaration_pos = TokenPos();
-  } else if (is_patch_source() &&
-      (CurrentToken() == Token::kIDENT) &&
-      CurrentLiteral()->Equals("patch")) {
-    if (FLAG_warn_patch) {
-      ReportWarning("deprecated use of patch 'keyword'");
-    }
-    ConsumeToken();
-    is_patch = true;
   } else if (CurrentToken() == Token::kABSTRACT) {
     is_abstract = true;
     ConsumeToken();
@@ -4826,11 +4818,7 @@ void Parser::ParseClassDefinition(const Class& cls) {
   is_top_level_ = true;
   String& class_name = String::Handle(Z, cls.Name());
   SkipMetadata();
-  if (is_patch_source() &&
-      (CurrentToken() == Token::kIDENT) &&
-      CurrentLiteral()->Equals("patch")) {
-    ConsumeToken();
-  } else if (CurrentToken() == Token::kABSTRACT) {
+  if (CurrentToken() == Token::kABSTRACT) {
     ConsumeToken();
   }
   ExpectToken(Token::kCLASS);
@@ -5707,15 +5695,6 @@ void Parser::ParseTopLevelFunction(TopLevel* top_level,
   if (is_patch_source() && IsPatchAnnotation(metadata_pos)) {
     is_patch = true;
     metadata_pos = TokenPosition::kNoSource;
-  } else if (is_patch_source() &&
-      (CurrentToken() == Token::kIDENT) &&
-      CurrentLiteral()->Equals("patch") &&
-      (LookaheadToken(1) != Token::kLPAREN)) {
-    if (FLAG_warn_patch) {
-      ReportWarning("deprecated use of patch 'keyword'");
-    }
-    ConsumeToken();
-    is_patch = true;
   } else if (CurrentToken() == Token::kEXTERNAL) {
     ConsumeToken();
     is_external = true;
@@ -5847,14 +5826,6 @@ void Parser::ParseTopLevelAccessor(TopLevel* top_level,
   if (is_patch_source() && IsPatchAnnotation(metadata_pos)) {
     is_patch = true;
     metadata_pos = TokenPosition::kNoSource;
-  } else if (is_patch_source() &&
-      (CurrentToken() == Token::kIDENT) &&
-      CurrentLiteral()->Equals("patch")) {
-    if (FLAG_warn_patch) {
-      ReportWarning("deprecated use of patch 'keyword'");
-    }
-    ConsumeToken();
-    is_patch = true;
   } else if (CurrentToken() == Token::kEXTERNAL) {
     ConsumeToken();
     is_external = true;
@@ -6398,9 +6369,6 @@ void Parser::ParseTopLevel() {
     } else if ((CurrentToken() == Token::kABSTRACT) &&
         (LookaheadToken(1) == Token::kCLASS)) {
       ParseClassDeclaration(pending_classes, tl_owner, metadata_pos);
-    } else if (is_patch_source() && IsSymbol(Symbols::Patch()) &&
-               (LookaheadToken(1) == Token::kCLASS)) {
-      ParseClassDeclaration(pending_classes, tl_owner, metadata_pos);
     } else {
       set_current_class(toplevel_class);
       if (IsVariableDeclaration()) {
@@ -8366,18 +8334,10 @@ bool Parser::IsFunctionDeclaration() {
   bool is_external = false;
   TokenPosScope decl_pos(this);
   SkipMetadata();
-  if (is_top_level_) {
-    if (is_patch_source() &&
-        (CurrentToken() == Token::kIDENT) &&
-        CurrentLiteral()->Equals("patch") &&
-        (LookaheadToken(1) != Token::kLPAREN)) {
-      // Skip over 'patch' for top-level function declarations in patch sources.
-      ConsumeToken();
-    } else if (CurrentToken() == Token::kEXTERNAL) {
-      // Skip over 'external' for top-level function declarations.
-      is_external = true;
-      ConsumeToken();
-    }
+  if ((is_top_level_) && (CurrentToken() == Token::kEXTERNAL)) {
+    // Skip over 'external' for top-level function declarations.
+    is_external = true;
+    ConsumeToken();
   }
   const TokenPosition type_or_name_pos = TokenPos();
   if (TryParseReturnType()) {
@@ -8417,9 +8377,7 @@ bool Parser::IsFunctionDeclaration() {
 
 bool Parser::IsTopLevelAccessor() {
   const TokenPosScope saved_pos(this);
-  if (is_patch_source() && IsSymbol(Symbols::Patch())) {
-    ConsumeToken();
-  } else if (CurrentToken() == Token::kEXTERNAL) {
+  if (CurrentToken() == Token::kEXTERNAL) {
     ConsumeToken();
   }
   if ((CurrentToken() == Token::kGET) || (CurrentToken() == Token::kSET)) {