[Fuchsia] Give VMOs names

runtime/vm/virtual_memory_fuchsia.cc

Index: runtime/vm/virtual_memory_fuchsia.cc
diff --git a/runtime/vm/virtual_memory_fuchsia.cc b/runtime/vm/virtual_memory_fuchsia.cc
index bc708ec8516e588d9ba1a2f2380ef65e93505c82..a364e2806342499865f42716b1154dac5d5fceb5 100644
--- a/runtime/vm/virtual_memory_fuchsia.cc
+++ b/runtime/vm/virtual_memory_fuchsia.cc
@@ -201,7 +201,10 @@ bool VirtualMemory::FreeSubSegment(int32_t handle,
 }
 
 
-bool VirtualMemory::Commit(uword addr, intptr_t size, bool executable) {
+bool VirtualMemory::Commit(uword addr,
+                           intptr_t size,
+                           bool executable,
+                           const char* name) {
   ASSERT(Contains(addr));
   ASSERT(Contains(addr + size) || (addr + size == end()));
   mx_handle_t vmo = MX_HANDLE_INVALID;
@@ -212,6 +215,15 @@ bool VirtualMemory::Commit(uword addr, intptr_t size, bool executable) {
     return false;
   }
 
+  if (name != NULL) {
+    status = mx_object_set_property(vmo, MX_PROP_NAME, name, strlen(name));
+    if (status != NO_ERROR) {

[abarth, 2017/06/09 19:46:40]

The pattern we've been using is to ignore errors on setting the name.

[zra, 2017/06/09 20:10:22]

Done.

+      mx_handle_close(vmo);
+      LOG_ERR("mx_object_set_property on vmo failed: %s\n",
+          mx_status_get_string(status));
+    }
+  }
+
   mx_handle_t vmar = static_cast<mx_handle_t>(handle());
   const size_t offset = addr - start();
   const uint32_t flags = MX_VM_FLAG_SPECIFIC | MX_VM_FLAG_PERM_READ |