p2p: Re-enable p2p unittests on update_engine.

These tests were disabled because they fail on systems where
fallocate is not supported on /tmp. Now that all the test
infrastructure is running precise we can re-enable these tests.

BUG=chromium:281496
TEST=run tests on peppy-paladin (failing before)

Change-Id: Ia9a53448ed9c357ff15619ddad255e616ec81871
Reviewed-on: https://chromium-review.googlesource.com/170028
Tested-by: Alex Deymo <deymo@chromium.org>
Reviewed-by: Chris Sosa <sosa@chromium.org>
Commit-Queue: Alex Deymo <deymo@chromium.org>
diff --git a/download_action_unittest.cc b/download_action_unittest.cc
index 558fc87..432cb16 100644
--- a/download_action_unittest.cc
+++ b/download_action_unittest.cc
@@ -546,11 +546,6 @@
   off_t start_at_offset_;
 };
 
-// TODO(zeuthen): Some builders do not support fallocate(2) or xattrs
-// in the tmp directories where the code runs so comment out these
-// tests for now. See http://crbug.com/281496
-#if 0
-
 TEST_F(P2PDownloadActionTest, IsWrittenTo) {
   SetupDownload(0);    // starting_offset
   StartDownload(true); // use_p2p_to_share
@@ -605,7 +600,6 @@
   EXPECT_EQ(data_.substr(1000), p2p_file_contents.substr(1000));
 }
 
-
 TEST_F(P2PDownloadActionTest, DeletePartialP2PFileIfResumingWithoutP2P) {
   SetupDownload(1000); // starting_offset
 
@@ -630,6 +624,4 @@
   EXPECT_EQ(p2p_manager_->CountSharedFiles(), 0);
 }
 
-#endif // http://crbug.com/281496
-
 }  // namespace chromeos_update_engine
diff --git a/p2p_manager_unittest.cc b/p2p_manager_unittest.cc
index 6bbe856..ce8d644 100644
--- a/p2p_manager_unittest.cc
+++ b/p2p_manager_unittest.cc
@@ -202,11 +202,6 @@
   EXPECT_EQ(manager->CountSharedFiles(), 3);
 }
 
-// TODO(zeuthen): Some builders do not support fallocate(2) or xattrs
-// in the tmp directories where the code runs so comment out these
-// tests for now. See http://crbug.com/281496
-#if 0
-
 static bool CheckP2PFile(const string& p2p_dir, const string& file_name,
                          ssize_t expected_size, ssize_t expected_size_xattr) {
   string path = p2p_dir + "/" + file_name;
@@ -367,8 +362,6 @@
   EXPECT_FALSE(visible);
 }
 
-#endif // http://crbug.com/281496
-
 // This is a little bit ugly but short of mocking a 'p2p' service this
 // will have to do. E.g. we essentially simulate the various
 // behaviours of initctl(8) that we rely on.