Fix the new Mojo EDK's mojo_system_unittests to pass in release builds and also on Linux.

mojo/edk/system/handle_table.cc

Index: mojo/edk/system/handle_table.cc
diff --git a/mojo/edk/system/handle_table.cc b/mojo/edk/system/handle_table.cc
index a9774c865913819a53bc86939a68cecd1c26108f..bb2f0df78b486fdf4fd23f090dd88dc9f548bdc6 100644
--- a/mojo/edk/system/handle_table.cc
+++ b/mojo/edk/system/handle_table.cc
@@ -81,7 +81,7 @@ bool HandleTable::AddDispatcherVector(const DispatcherVector& dispatchers,
   size_t max_handle_table_size = GetConfiguration().max_handle_table_size;
 
   DCHECK_LE(dispatchers.size(), max_message_num_handles);
-  DCHECK(handles);
+  CHECK(handles);

[jam, 2015/12/03 03:42:36]

for here and below, there were death tests that expected the check to fire. for
release they were compiled out.

   DCHECK_LT(
       static_cast<uint64_t>(max_handle_table_size) + max_message_num_handles,
       std::numeric_limits<size_t>::max())
@@ -107,7 +107,7 @@ MojoResult HandleTable::MarkBusyAndStartTransport(
     uint32_t num_handles,
     std::vector<DispatcherTransport>* transports) {
   DCHECK_NE(disallowed_handle, MOJO_HANDLE_INVALID);
-  DCHECK(handles);
+  CHECK(handles);
   DCHECK_LE(num_handles, GetConfiguration().max_message_num_handles);
   DCHECK(transports);
   DCHECK_EQ(transports->size(), num_handles);