libhwui: Handle the blurImage() implement once RS::init fail

Once the RS::init failed, go through the original single thread path,
this will avoid blocking the main thread(ANR), but we also should have
some implement in RenderScript component.

Change-Id: I3a21395ffd5bc144c15254893f425b1dd2643ba4
Signed-off-by: Shenghua Lu <shenghua.lu@intel.com>
Signed-off-by: Shuo Gao <shuo.gao@intel.com>