fix PDF load issue (414827)

pdf/document_loader.cc

 // Copyright (c) 2010 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "pdf/document_loader.h"
 
 #include "base/logging.h"
 #include "base/strings/string_util.h"
 #include "net/http/http_util.h"
 #include "ppapi/c/pp_errors.h"
@@ skipping 280 matching lines @@
 
   return request;
 }
 
 void DocumentLoader::DidOpen(int32_t result) {
   if (result != PP_OK) {
     NOTREACHED();
     return;
   }
 
+  int32_t http_code = loader_.GetResponseInfo().GetStatusCode();
+  if (http_code >= 400 && http_code < 500) {
+    // Error accessing resource. 4xx error indicate subsequent requests
+    // will fail too.
+    // E.g. resource has been removed from the server while loading it.
+    // https://code.google.com/p/chromium/issues/detail?id=414827
+    return;
+  }
+
   is_multipart_ = false;
   current_chunk_size_ = 0;
   current_chunk_read_ = 0;
 
   pp::Var headers_var = loader_.GetResponseInfo().GetHeaders();
   std::string headers;
   if (headers_var.is_string())
     headers = headers_var.AsString();
 
   std::string boundary = GetMultiPartBoundary(headers);
@@ skipping 184 matching lines @@
 uint32 DocumentLoader::GetRequestSize() const {
   // Document loading strategy:
   // For first 10 requests, we use 32k chunk sizes, for the next 10 requests we
   // double the size (64k), and so on, until we cap max request size at 2M for
   // 71 or more requests.
   uint32 limited_count = std::min(std::max(requests_count_, 10u), 70u);
   return 32*1024 * (1 << ((limited_count - 1) / 10u));
 }
 
 }  // namespace chrome_pdf