[sqlite] Remove WebDatabase externs and depend on what you use.

Source/modules/webdatabase/sqlite/SQLiteFileSystemPosix.cpp

Index: Source/modules/webdatabase/sqlite/SQLiteFileSystemPosix.cpp
diff --git a/Source/modules/webdatabase/sqlite/SQLiteFileSystemPosix.cpp b/Source/modules/webdatabase/sqlite/SQLiteFileSystemPosix.cpp
index 3a96c0e959ccdd904ef60432d1e04b90e051a31e..b73ec035ddc9fdc39b013e5d66202ae8a6b5677f 100644
--- a/Source/modules/webdatabase/sqlite/SQLiteFileSystemPosix.cpp
+++ b/Source/modules/webdatabase/sqlite/SQLiteFileSystemPosix.cpp
@@ -28,6 +28,9 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+// Expose chromium_sqlite3_* functions from Chromium's patched SQLite.
+#define CHROMIUM_SQLITE_INTERNALS
+
 #include "config.h"
 #include "modules/webdatabase/sqlite/SQLiteFileSystem.h"
 
@@ -38,15 +41,6 @@
 #include <string.h>
 #include <unistd.h>
 
-// Defined in Chromium's codebase in third_party/sqlite/src/os_unix.c
-extern "C" {
-void chromium_sqlite3_initialize_unix_sqlite3_file(sqlite3_file* file);
-int chromium_sqlite3_fill_in_unix_sqlite3_file(sqlite3_vfs* vfs, int fd, int dirfd, sqlite3_file* file, const char* fileName, int noLock);
-int chromium_sqlite3_get_reusable_file_handle(sqlite3_file* file, const char* fileName, int flags, int* fd);
-void chromium_sqlite3_update_reusable_file_handle(sqlite3_file* file, int fd, int flags);
-void chromium_sqlite3_destroy_reusable_file_handle(sqlite3_file* file);
-}
-
 namespace blink {
 
 // Chromium's Posix implementation of SQLite VFS