remove usage of poison_patch from sqlite.

Google gears team implemented a patch to sqlite called "poison the header".
It got included in sqlite android shipped.

This patch is meant to corrupt the database header if some sqlite process
concludes that the database is corrupt. Thereafter, any other sqlite process
opening the same database file would quickly see the corruption and exit.

I am not convinced that this is a useful patch for Android.
And, it patch didn't make it to the open source version of sqlite.

could it be causing previously nonexisting
database corruption, by incorrectly poisoning the database header? thats
what I am suspecting.
diff --git a/dist/Android.mk b/dist/Android.mk
index 0200276..ec01ec6 100644
--- a/dist/Android.mk
+++ b/dist/Android.mk
@@ -17,7 +17,7 @@
 LOCAL_LDLIBS += -lpthread -ldl
 endif
 
-LOCAL_CFLAGS += -DHAVE_USLEEP=1 -DSQLITE_DEFAULT_JOURNAL_SIZE_LIMIT=1048576 -DSQLITE_THREADSAFE=1 -DNDEBUG=1 -DSQLITE_ENABLE_MEMORY_MANAGEMENT=1 -DSQLITE_DEFAULT_AUTOVACUUM=1 -DSQLITE_TEMP_STORE=3 -DSQLITE_ENABLE_FTS3 -DSQLITE_ENABLE_FTS3_BACKWARDS -DSQLITE_ENABLE_POISON
+LOCAL_CFLAGS += -DHAVE_USLEEP=1 -DSQLITE_DEFAULT_JOURNAL_SIZE_LIMIT=1048576 -DSQLITE_THREADSAFE=1 -DNDEBUG=1 -DSQLITE_ENABLE_MEMORY_MANAGEMENT=1 -DSQLITE_DEFAULT_AUTOVACUUM=1 -DSQLITE_TEMP_STORE=3 -DSQLITE_ENABLE_FTS3 -DSQLITE_ENABLE_FTS3_BACKWARDS
 
 ifneq ($(TARGET_SIMULATOR),true)
 LOCAL_SHARED_LIBRARIES := libdl
@@ -86,7 +86,7 @@
 
 LOCAL_SRC_FILES := $(common_src_files) shell.c
 
-LOCAL_CFLAGS += -DHAVE_USLEEP=1 -DSQLITE_DEFAULT_JOURNAL_SIZE_LIMIT=1048576 -DSQLITE_THREADSAFE=1 -DNDEBUG=1 -DSQLITE_ENABLE_MEMORY_MANAGEMENT=1 -DNO_ANDROID_FUNCS=1 -DSQLITE_TEMP_STORE=3 -DSQLITE_ENABLE_FTS3 -DSQLITE_ENABLE_FTS3_BACKWARDS -DSQLITE_ENABLE_POISON
+LOCAL_CFLAGS += -DHAVE_USLEEP=1 -DSQLITE_DEFAULT_JOURNAL_SIZE_LIMIT=1048576 -DSQLITE_THREADSAFE=1 -DNDEBUG=1 -DSQLITE_ENABLE_MEMORY_MANAGEMENT=1 -DNO_ANDROID_FUNCS=1 -DSQLITE_TEMP_STORE=3 -DSQLITE_ENABLE_FTS3 -DSQLITE_ENABLE_FTS3_BACKWARDS
 
 LOCAL_C_INCLUDES := $(LOCAL_PATH)/../android