Fix content verification code for undreadable and deleted files.

extensions/browser/content_verify_job.cc

 // Copyright 2014 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 "extensions/browser/content_verify_job.h"
 
 #include <algorithm>
 
 #include "base/metrics/histogram_macros.h"
 #include "base/stl_util.h"
@@ skipping 125 matching lines @@
   if (hashes_ready_) {
     if (!FinishBlock())
       DispatchFailureCallback(HASH_MISMATCH);
     else if (g_test_observer)
       g_test_observer->JobFinished(hash_reader_->extension_id(),
                                    hash_reader_->relative_path(), failed_);
   }
 }
 
 bool ContentVerifyJob::FinishBlock() {
-  if (current_hash_byte_count_ <= 0)
+  if (!done_reading_ && current_hash_byte_count_ <= 0)

[Devlin, 2017/03/24 02:01:44]

unrelated to this cl, but when can current_hash_byte_count_ be < 0?

[lazyboy, 2017/03/24 18:27:47]

Yes I noticed this and didn't want to change it at first.
Shouldn't ever be < 0, changed to == 0.

     return true;
+  if (!current_hash_) {
+    // This happens when we fail to read the resource, compute empty content's

[Devlin, 2017/03/24 02:01:45]

nitty nit: s/,/;||.

[lazyboy, 2017/03/24 18:27:47]

Done.

+    // hash in this case.
+    current_hash_ = crypto::SecureHash::Create(crypto::SecureHash::SHA256);
+  }
   std::string final(crypto::kSHA256Length, 0);
   current_hash_->Finish(base::string_as_array(& final), final.size());
   current_hash_.reset();
   current_hash_byte_count_ = 0;
 
   int block = current_block_++;
 
   const std::string* expected_hash = NULL;
   if (!hash_reader_->GetHashForBlock(block, &expected_hash) ||
       *expected_hash != final)
@@ skipping 55 matching lines @@
             << " reason:" << reason;
     failure_callback_.Run(reason);
     failure_callback_.Reset();
   }
   if (g_test_observer)
     g_test_observer->JobFinished(
         hash_reader_->extension_id(), hash_reader_->relative_path(), failed_);
 }
 
 }  // namespace extensions