[websql] Guard against vfs method deprecation.

third_party/WebKit/Source/modules/webdatabase/sqlite/SQLiteFileSystemPosix.cpp

Index: third_party/WebKit/Source/modules/webdatabase/sqlite/SQLiteFileSystemPosix.cpp
diff --git a/third_party/WebKit/Source/modules/webdatabase/sqlite/SQLiteFileSystemPosix.cpp b/third_party/WebKit/Source/modules/webdatabase/sqlite/SQLiteFileSystemPosix.cpp
index 45487c262ed1ae20797c3227cb825ad317aa18f3..7a234bd118c8a0f03aa0c9a03fb8cbafa1ea6f18 100644
--- a/third_party/WebKit/Source/modules/webdatabase/sqlite/SQLiteFileSystemPosix.cpp
+++ b/third_party/WebKit/Source/modules/webdatabase/sqlite/SQLiteFileSystemPosix.cpp
@@ -303,8 +303,9 @@ int chromiumCurrentTime(sqlite3_vfs* vfs, double* prNow)
 
 int chromiumGetLastError(sqlite3_vfs* vfs, int e, char* s)
 {
-    sqlite3_vfs* wrappedVfs = static_cast<sqlite3_vfs*>(vfs->pAppData);
-    return wrappedVfs->xGetLastError(wrappedVfs, e, s);
+    // xGetLastError() has never been used by SQLite.  The implementation in os_win.c indicates this is a reasonable implementation.
+    *s = '\0';
+    return 0;
 }
 
 } // namespace
@@ -312,6 +313,13 @@ int chromiumGetLastError(sqlite3_vfs* vfs, int e, char* s)
 void SQLiteFileSystem::registerSQLiteVFS()
 {
     sqlite3_vfs* wrappedVfs = sqlite3_vfs_find("unix");
+
+    // These are implemented by delegating to |wrappedVfs|.
+    // TODO(shess): Implement local versions.
+    ASSERT(wrappedVfs->xRandomness);
+    ASSERT(wrappedVfs->xSleep);
+    ASSERT(wrappedVfs->xCurrentTime);
+
     static sqlite3_vfs chromium_vfs = {
         1,
         sizeof(chromiumVfsFile),