Remove uses of gfe2::test::GenerateBody from QUIC code and use the string fill constructor instead.

net/quic/core/quic_headers_stream_test.cc

Index: net/quic/core/quic_headers_stream_test.cc
diff --git a/net/quic/core/quic_headers_stream_test.cc b/net/quic/core/quic_headers_stream_test.cc
index 167dfcefe2c2b6e6ccc9606473c4f039f701edd5..d1f728a659077a35d78ba00eeb1184cba90f7974 100644
--- a/net/quic/core/quic_headers_stream_test.cc
+++ b/net/quic/core/quic_headers_stream_test.cc
@@ -949,7 +949,6 @@ TEST_P(QuicHeadersStreamTest, WritevStreamData) {
   QuicStreamId id = kClientDataStreamId1;
   QuicStreamOffset offset = 0;
   struct iovec iov;
-  string data;
 
   // This test will issue a write that will require fragmenting into
   // multiple HTTP/2 DATA frames.
@@ -958,7 +957,7 @@ TEST_P(QuicHeadersStreamTest, WritevStreamData) {
       kSpdyInitialFrameSizeLimit * kMinDataFrames + 1024;
   // Set headers stream send window large enough for data written below.
   headers_stream_->flow_controller()->UpdateSendWindowOffset(data_len * 2 * 4);
-  test::GenerateBody(&data, data_len);
+  string data(data_len, 'a');
 
   for (bool fin : {true, false}) {
     for (bool use_ack_listener : {true, false}) {
@@ -1022,7 +1021,6 @@ TEST_P(QuicHeadersStreamTest, WritevStreamDataSendBlocked) {
   QuicStreamId id = kClientDataStreamId1;
   QuicStreamOffset offset = 0;
   struct iovec iov;
-  string data;
 
   // This test will issue a write that will require fragmenting into
   // multiple HTTP/2 DATA frames.  It will ensure that only 1 frame
@@ -1033,7 +1031,7 @@ TEST_P(QuicHeadersStreamTest, WritevStreamDataSendBlocked) {
   const size_t data_len = kSpdyInitialFrameSizeLimit * kMinDataFrames + 1024;
   // Set headers stream send window large enough for data written below.
   headers_stream_->flow_controller()->UpdateSendWindowOffset(data_len * 2 * 4);
-  test::GenerateBody(&data, data_len);
+  string data(data_len, 'a');
 
   bool fin = true;
   // So force the underlying |WritevData| to consume only 1 byte.