Add test to ensure that URLs that redirect inside the PDF plugin fail to load

pdf/document_loader.cc

Index: pdf/document_loader.cc
diff --git a/pdf/document_loader.cc b/pdf/document_loader.cc
index ea4b664b27b53afccc3f6ccb50e23eae456a7ab9..ebc7174e84e3cf445c61c83b5141e92cc1ba86bb 100644
--- a/pdf/document_loader.cc
+++ b/pdf/document_loader.cc
@@ -19,6 +19,20 @@ namespace chrome_pdf {
 
 namespace {
 
+// Return true if the HTTP response of |loader| is a succesful one and loading

[Lei Zhang, 2016/11/03 07:10:45]

typo

[raymes, 2016/11/07 03:25:44]

Done.

+// should continue. 4xx error indicate subsequent requests will fail too.
+// e.g. resource has been removed from the server while loading it. 301
+// indicates a redirect was returned which won't be successful because we
+// disable following redirects for PDF loading (we assume they are already
+// resolved by the browser.
+bool ResponseStatusSuccess(const pp::URLLoader& loader) {
+  int32_t http_code = loader.GetResponseInfo().GetStatusCode();
+  if ((http_code >= 400 && http_code < 500) || http_code == 301)

[Lei Zhang, 2016/11/03 07:10:45]

Just: return (http_code < 400 && http_code != 301) || http_code >= 500;
Or: keep the logic and change the method to ResponseStatusFailed().

[raymes, 2016/11/07 03:25:44]

Done.

+    return false;
+
+  return true;
+}
+
 // If the headers have a byte-range response, writes the start and end
 // positions and returns true if at least the start position was parsed.
 // The end position will be set to 0 if it was not found or parsed from the
@@ -102,6 +116,10 @@ bool DocumentLoader::Init(const pp::URLLoader& loader,
   url_ = url;
   loader_ = loader;
 
+  // Check that the initial response status is a valid one.
+  if (!ResponseStatusSuccess(loader_))
+    return false;
+
   std::string response_headers;
   if (!headers.empty()) {
     response_headers = headers;
@@ -358,12 +376,8 @@ void DocumentLoader::DidOpen(int32_t result) {
     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
+  if (!ResponseStatusSuccess(loader_)) {
+    client_->DocumentLoadFailed();
     return;
   }