Add denpendencies to AppSearch CmakeLists.txt commands. To allow it re-make when file is updated.

Bug: 170611579
Test: Manually: 1: checkout on an old branch
2. add denpendencies to cmake (changing cmakelists will invalidate a lot of caches)
3. build and generate cxx files
4. patch the head branch with the latest version
5. build again w/o any error.

Change-Id: Ie47826cb74a84160ef0646abbfd77869801f2c35
diff --git a/.gitignore b/.gitignore
index f57bd5e..962fbd5 100644
--- a/.gitignore
+++ b/.gitignore
@@ -3,3 +3,4 @@
 
 # Files
 *.iml
+*.cmake.gen
\ No newline at end of file