Fix initialization of AAC presentation struct

Otherwise the new size checks trip on this.

Bug: 27207275
Change-Id: I1f8f01097e3a88ff041b69279a6121be842f1766

void ACodec::initiateCreateInputSurface() {
 (new AMessage(kWhatCreateInputSurface, this))->post();
}

void ACodec::initiateCreateInputSurface() {
 (new AMessage(kWhatCreateInputSurface, this))->post();
}
