Android: hardcode leveldb revision

Newest leveldb commit breaks build.
With no fix in sight, there is no other way
than to fall back to the last working leveldb
revision, and hardcode it.

Workaround for upstream bug

https://github.com/google/leveldb/issues/340

build/android/Makefile

@@ -90,6 +90,7 @@ LEVELDB_LIB = $(LEVELDB_DIR)libleveldb.a
 LEVELDB_TIMESTAMP = $(LEVELDB_DIR)/timestamp
 LEVELDB_TIMESTAMP_INT = $(ROOT)/deps/leveldb_timestamp
 LEVELDB_URL_GIT = https://github.com/google/leveldb
+LEVELDB_COMMIT = 2d0320a458d0e6a20fff46d5f80b18bfdcce7018
 
 OPENAL_DIR = $(ROOT)/deps/openal-soft/
 OPENAL_LIB = $(OPENAL_DIR)libs/$(TARGET_ABI)/libopenal.so
@@ -363,6 +364,8 @@ leveldb_download :
 		mkdir -p ${ROOT}/deps;                                                 \
 		cd ${ROOT}/deps ;                                                      \
 		git clone ${LEVELDB_URL_GIT} || exit 1;                                \
+		cd ${LEVELDB_DIR} || exit 1;                                           \
+		git checkout ${LEVELDB_COMMIT} || exit 1;                              \
 	fi
 
 leveldb : $(LEVELDB_LIB)