Delete and recreate the sync database if it is corrupt.

chrome/browser/sync/syncable/directory_backing_store_unittest.cc

Index: chrome/browser/sync/syncable/directory_backing_store_unittest.cc
diff --git a/chrome/browser/sync/syncable/directory_backing_store_unittest.cc b/chrome/browser/sync/syncable/directory_backing_store_unittest.cc
index bf5dfde678162d8a3a2a6d7ee9d780e1523e4ecb..777a163a09d9b42c4c5d0f4279e1ca10ab1c7197 100644
--- a/chrome/browser/sync/syncable/directory_backing_store_unittest.cc
+++ b/chrome/browser/sync/syncable/directory_backing_store_unittest.cc
@@ -10,6 +10,7 @@
 #include "app/sql/statement.h"
 #include "app/sql/transaction.h"
 #include "base/file_path.h"
+#include "base/file_util.h"
 #include "base/scoped_ptr.h"
 #include "base/scoped_temp_dir.h"
 #include "base/stl_util-inl.h"
@@ -870,4 +871,27 @@ TEST_F(DirectoryBackingStoreTest, ModelTypeIds) {
   }
 }
 
+TEST_F(DirectoryBackingStoreTest, Corruption) {
+  {
+    scoped_ptr<DirectoryBackingStore> dbs(
+        new DirectoryBackingStore(GetUsername(), GetDatabasePath()));
+    EXPECT_TRUE(dbs->BeginLoad());
+  }
+  std::string bad_data("BAD DATA");
+  EXPECT_TRUE(file_util::WriteFile(GetDatabasePath(), bad_data.data(),
+                                   bad_data.size()));
+  {
+    scoped_ptr<DirectoryBackingStore> dbs(
+        new DirectoryBackingStore(GetUsername(), GetDatabasePath()));
+
+    // In release mode, we expect the sync database to nuke itself and start
+    // over if it detects invalid/corrupted data.
+#if defined(NDEBUG)
+    EXPECT_TRUE(dbs->BeginLoad());
+#else
+    EXPECT_DEATH(dbs->BeginLoad(), "sqlite error");
+#endif
+  }
+}
+
 }  // namespace syncable