A crude cut at incorporating stream 1 footer read into stream 0 read.

net/disk_cache/simple/simple_entry_impl.cc

Index: net/disk_cache/simple/simple_entry_impl.cc
diff --git a/net/disk_cache/simple/simple_entry_impl.cc b/net/disk_cache/simple/simple_entry_impl.cc
index 62347507f8d8d61b2e272901670212bbe5399cbf..03e2d4c9e7f4b205084a135d02002ed0d047f1f5 100644
--- a/net/disk_cache/simple/simple_entry_impl.cc
+++ b/net/disk_cache/simple/simple_entry_impl.cc
@@ -1484,6 +1484,8 @@ int SimpleEntryImpl::SetStream0Data(net::IOBuffer* buf,
   int data_size = GetDataSize(0);
   if (offset == 0 && truncate) {
     RecordHeaderSizeChange(cache_type_, data_size, buf_len);
+    // Undo some of the offset weirdness from SimpleSynchronousEntry
+    stream_0_data_->set_offset(0);
     stream_0_data_->SetCapacity(buf_len);
     memcpy(stream_0_data_->data(), buf->data(), buf_len);
     data_size_[0] = buf_len;
@@ -1491,7 +1493,7 @@ int SimpleEntryImpl::SetStream0Data(net::IOBuffer* buf,
     RecordUnexpectedStream0Write(cache_type_);
     const int buffer_size =
         truncate ? offset + buf_len : std::max(offset + buf_len, data_size);
-    stream_0_data_->SetCapacity(buffer_size);
+    stream_0_data_->SetCapacity(buffer_size + stream_0_data_->offset());
     // If |stream_0_data_| was extended, the extension until offset needs to be
     // zero-filled.
     const int fill_size = offset <= data_size ? 0 : offset - data_size;