LLDB uses process_vm_readv quite extensively (it's an order of magnitude faster than PTRACE_PEEKDATA). Add a bit more tests of the function to make sure it stays working. Change-Id: I64e17e6d56842f118a9485e3a18f42ca5e1b7577 Test: run the new test
Bug: http://b/12612572 Change-Id: I38ff2684d69bd0fe3f21b1d371b88fa60d5421cb
Bug: http://b/21761353 Change-Id: Ic8ef3f241d62d2a4271fbc783c8af50257bac498