am e97682be: am a1a22b57: am e67b5848: am 4956c0fe: am 5b85b1d4: libutils: fix overflow in String8::allocFromUTF8

* commit 'e97682be0634fe773f70097bc518e5d034efe8f7':
  libutils: fix overflow in String8::allocFromUTF8