Reland "binder: Parcel avoid too small initial allocation"

Bug: 150149045
This reverts commit ce326209.

Reason for revert: reland original fix after fixing android.os.cts.ParcelTest

The place where the default size is changed here from the original CL.
Now, when explicit setDataCapacity calls are made, we no longer use an
artificially larger size.

Test: atest android.os.cts.ParcelTest
Test: atest binderAllocationLimits

Change-Id: I08c5eeb3be0b61ccf2f5e34b5bc7b45f58f8cbcb