Update git submodules

* Update trusty/user/base from branch 'master'
  to 1b5a3949fc3311ecc2c862068795f2766e3e3601
  - googletest: Add missing dependency on libcxx
    
    This dependency was missing but the build was including it anyway and
    happened to work.
    
    Test: build.py
    Bug: None
    Change-Id: Ie53ce96eb31b2ba01580aa90ae433f1083039c9f
    
diff --git a/trusty/user/base b/trusty/user/base
index 6bed0ad..1b5a394 160000
--- a/trusty/user/base
+++ b/trusty/user/base
@@ -1 +1 @@
-Subproject commit 6bed0adc88fe14195014ff3e00f648be7a74d96c
+Subproject commit 1b5a3949fc3311ecc2c862068795f2766e3e3601