Correctly initialize monitors for 32-bit

Fully initialize lock_owner... fields. The only one that's critical
here is the lock_owner_ field itself, but let's be consistent.

A randomly set lock_owner_ field can cause GetLockOwnerInfo() to
spin indefinitely.

Bug: 148094637
Test: TreeHugger
Change-Id: I50cab5ba412a2a8113e44c5f05c2990c5d7d101f
diff --git a/runtime/monitor.cc b/runtime/monitor.cc
index 6b05e28..8190960 100644
--- a/runtime/monitor.cc
+++ b/runtime/monitor.cc
@@ -99,8 +99,11 @@
       wait_set_(nullptr),
       wake_set_(nullptr),
       hash_code_(hash_code),
+      lock_owner_(nullptr),
       lock_owner_method_(nullptr),
       lock_owner_dex_pc_(0),
+      lock_owner_sum_(0),
+      lock_owner_request_(nullptr),
       monitor_id_(MonitorPool::ComputeMonitorId(this, self)) {
 #ifdef __LP64__
   DCHECK(false) << "Should not be reached in 64b";
@@ -126,6 +129,9 @@
       wake_set_(nullptr),
       hash_code_(hash_code),
       lock_owner_(nullptr),
+      lock_owner_method_(nullptr),
+      lock_owner_dex_pc_(0),
+      lock_owner_sum_(0),
       lock_owner_request_(nullptr),
       monitor_id_(id) {
 #ifdef __LP64__