[net/dns] Handle TC bit on DNS response in DnsTransaction.

net/dns/dns_response.h

Index: net/dns/dns_response.h
diff --git a/net/dns/dns_response.h b/net/dns/dns_response.h
index cb61e1fb1efbbb2c2b9b85f386e669536faa0a1c..82476fd373597c74c21a097bbd488f33c775e3be 100644
--- a/net/dns/dns_response.h
+++ b/net/dns/dns_response.h
@@ -95,10 +95,11 @@ class NET_EXPORT_PRIVATE DnsResponse {
     DNS_PARSE_RESULT_MAX,      // Bounding value for histograms.
   };
 
-  // Constructs an object with an IOBuffer large enough to read
-  // one byte more than largest possible response, to detect malformed
-  // responses.
+  // Constructs a response buffer large enough to store one byte more than
+  // largest possible response, to detect malformed responses.
   DnsResponse();
+  // Construct a response buffer of given length. Used for TCP transactions.

[mmenke, 2012/12/19 16:44:09]

nit:  For consistency, should start all constructor comments with same form of
"Construct".

[szym, 2012/12/19 23:35:56]

Done.

+  explicit DnsResponse(size_t length);
   // Constructs response from |data|. Used for testing purposes only!
   DnsResponse(const void* data, size_t length, size_t answer_offset);
   ~DnsResponse();
@@ -107,8 +108,8 @@ class NET_EXPORT_PRIVATE DnsResponse {
   // read.
   IOBufferWithSize* io_buffer() { return io_buffer_.get(); }
 
-  // Returns false if the packet is shorter than the header or does not match
-  // |query| id or question.
+  // Assuming the internal buffer holds |nbytes| bytes, returns true iff the
+  // packet matches the |query| id and question.
   bool InitParse(int nbytes, const DnsQuery& query);
 
   // Returns true if response is valid, that is, after successful InitParse.