[WebSocketExtensionParser] Have Consume.* methods return bool instead of using has_error()

net/websockets/websocket_extension_parser.h

Index: net/websockets/websocket_extension_parser.h
diff --git a/net/websockets/websocket_extension_parser.h b/net/websockets/websocket_extension_parser.h
index 6b2e4dc629873b50348d221283fe49d2afca5cc8..007040de291408aa411fa24eb172a7db6c6246e7 100644
--- a/net/websockets/websocket_extension_parser.h
+++ b/net/websockets/websocket_extension_parser.h
@@ -8,6 +8,7 @@
 #include <string>
 #include <vector>
 
+#include "base/compiler_specific.h"
 #include "base/strings/string_piece.h"
 #include "net/base/net_export.h"
 #include "net/websockets/websocket_extension.h"
@@ -23,28 +24,28 @@ class NET_EXPORT_PRIVATE WebSocketExtensionParser {
   //
   // There must be no newline characters in the input. LWS-concatenation must
   // have already been done before calling this method.
-  void Parse(const char* data, size_t size);
-  void Parse(const std::string& data) {
-    Parse(data.data(), data.size());
+  //
+  // Returns true if the method was successful (no syntax error was found).
+  bool Parse(const char* data, size_t size);
+  bool Parse(const std::string& data) {
+    return Parse(data.data(), data.size());
   }
 
-  // Returns true if the last Parse() method call encountered any syntax error.
-  bool has_error() const { return has_error_; }
   // Returns the result of the last Parse() method call.
   const std::vector<WebSocketExtension>& extensions() const {
     return extensions_;
   }
 
  private:
-  // TODO(tyoshino): Make the following methods return success/fail.
-  void Consume(char c);
-  void ConsumeExtension(WebSocketExtension* extension);
-  void ConsumeExtensionParameter(WebSocketExtension::Parameter* parameter);
-  void ConsumeToken(base::StringPiece* token);
-  void ConsumeQuotedToken(std::string* token);
+  WARN_UNUSED_RESULT bool Consume(char c);
+  WARN_UNUSED_RESULT bool ConsumeExtension(WebSocketExtension* extension);
+  WARN_UNUSED_RESULT bool ConsumeExtensionParameter(
+      WebSocketExtension::Parameter* parameter);
+  WARN_UNUSED_RESULT bool ConsumeToken(base::StringPiece* token);
+  WARN_UNUSED_RESULT bool ConsumeQuotedToken(std::string* token);
   void ConsumeSpaces();
-  bool Lookahead(char c);
-  bool ConsumeIfMatch(char c);
+  WARN_UNUSED_RESULT bool Lookahead(char c);
+  WARN_UNUSED_RESULT bool ConsumeIfMatch(char c);
   size_t UnconsumedBytes() const { return end_ - current_; }
 
   static bool IsControl(char c);
@@ -54,7 +55,6 @@ class NET_EXPORT_PRIVATE WebSocketExtensionParser {
   const char* current_;
   // The pointer of the end of the input string.
   const char* end_;
-  bool has_error_;
   std::vector<WebSocketExtension> extensions_;
 
   DISALLOW_COPY_AND_ASSIGN(WebSocketExtensionParser);