Let sqlite use fdatasync() on Linux-based systems

third_party/sqlite/sqlite.gyp

Index: third_party/sqlite/sqlite.gyp
diff --git a/third_party/sqlite/sqlite.gyp b/third_party/sqlite/sqlite.gyp
index ed64e98d8d0f733939f4f95b799b80fc29dd260e..206ff262a548bc01ca364172393aa242ae25f198 100644
--- a/third_party/sqlite/sqlite.gyp
+++ b/third_party/sqlite/sqlite.gyp
@@ -62,6 +62,12 @@
             'HAVE_USLEEP=1',
           ],
         }],
+        ['OS == "linux" or OS == "android"', {
+          'defines': [
+            # Linux provides fdatasync(), a faster equivalent of fsync().
+            'fdatasync=fdatasync',
+          ],
+        }],

[Scott Hess - ex-Googler, 2015/03/26 17:46:00]

I couldn't figure out if this should be here...

[Scott Hess - ex-Googler, 2015/03/26 21:51:07]

I was updating my Linux client, so I patched your CL in and on the
straight-Linux client, this doesn't hit the define, and strace shows fdatasync
being called, so this works.

And since I don't know where it should be, and GN will hopefully remove the need
for this file, I guess this is fine.

[hashimoto, 2015/03/27 05:15:02]

I chose this place because this |fdatasync| is used in the same place as
SQLITE_NO_SYNC (namely, full_fsync() function in sqlite3.c).

         ['use_system_sqlite', {
           'type': 'none',
           'direct_dependent_settings': {