Reland "Make compiler/optimizing/ symbols hidden."
This reverts commit 0a51605ddd81635135463dab08b6f7c21b58ffb0.
Reason for revert: Reland after some of the required work
was merged in other CLs.
Also address a TODO from the original CL to mark required
symbols with EXPORT in `intrinsic_objects.h`.
Also mark symbols in new files as HIDDEN.
Bug: 186902856
Test: m test-art-host-gtest
Test: testrunner.py --host --optimizing
Change-Id: I936d448983928af23614ca82c2d0bf9a645e2c52
diff --git a/compiler/optimizing/gvn.cc b/compiler/optimizing/gvn.cc
index c7cd223..a6ca057 100644
--- a/compiler/optimizing/gvn.cc
+++ b/compiler/optimizing/gvn.cc
@@ -23,7 +23,7 @@
#include "base/utils.h"
#include "side_effects_analysis.h"
-namespace art {
+namespace art HIDDEN {
/**
* A ValueSet holds instructions that can replace other instructions. It is updated