Thread IO safety: annotate file_util, and block IO thread from doing IO

- Mark functions in file_util_posix as requiring permission to perform
  disk actions.
- Mark the IO thread as disallowed from performing disk actions.
- Temporarily work around the protections in places where we currently
  have bugs.

BUG=59847,59849,60207,60211,60394
TEST=no dchecks in debug builds

Review URL: http://codereview.chromium.org/3872002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@63636 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 11 insertions, 0 deletions

diff --git a/chrome/browser/net/url_request_mock_http_job.cc b/chrome/browser/net/url_request_mock_http_job.cc
index a35cd1e..4029605 100644
--- a/chrome/browser/net/url_request_mock_http_job.cc
+++ b/chrome/browser/net/url_request_mock_http_job.cc
@@ -7,6 +7,7 @@
 #include "base/file_util.h"
 #include "base/message_loop.h"
 #include "base/string_util.h"
+#include "base/thread_restrictions.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/common/url_constants.h"
 #include "net/base/net_util.h"
@@ -87,6 +88,10 @@ bool URLRequestMockHTTPJob::IsRedirectResponse(GURL* location,
 // Private const version.
 void URLRequestMockHTTPJob::GetResponseInfoConst(
     net::HttpResponseInfo* info) const {
+  // We have to load our headers from disk, but we only use this class
+  // from tests, so allow these IO operations to happen on any thread.
+  base::ThreadRestrictions::ScopedAllowIO allow_io;
+
   FilePath header_file = FilePath(file_path_.value() + kMockHeaderFileSuffix);
   std::string raw_headers;
   if (!file_util::ReadFileToString(header_file, &raw_headers))
diff --git a/chrome/browser/net/url_request_mock_util.cc b/chrome/browser/net/url_request_mock_util.cc
index e6531f8..b3ac398 100644
--- a/chrome/browser/net/url_request_mock_util.cc
+++ b/chrome/browser/net/url_request_mock_util.cc
@@ -7,6 +7,7 @@
 #include <string>
 
 #include "base/path_service.h"
+#include "base/thread_restrictions.h"
 #include "chrome/browser/browser_thread.h"
 #include "chrome/browser/net/url_request_failed_dns_job.h"
 #include "chrome/browser/net/url_request_mock_http_job.h"
@@ -24,6 +25,11 @@ void SetUrlRequestMocksEnabled(bool enabled) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 
   if (enabled) {
+    // We have to look around for our helper files, but we only use
+    // this from tests, so allow these IO operations to happen
+    // anywhere.
+    base::ThreadRestrictions::ScopedAllowIO allow_io;
+
     URLRequestFilter::GetInstance()->ClearHandlers();
 
     URLRequestFailedDnsJob::AddUrlHandler();