Mark types used in template instantiatious explicitly as visible

cc/occlusion_tracker.h

Index: cc/occlusion_tracker.h
diff --git a/cc/occlusion_tracker.h b/cc/occlusion_tracker.h
index 1d549e709347a38a24d1e5bd8ef0367ba0a7f2e3..882c75aa315807d37b8ff3d8860a094158c07cba 100644
--- a/cc/occlusion_tracker.h
+++ b/cc/occlusion_tracker.h
@@ -6,6 +6,7 @@
 #define CC_OCCLUSION_TRACKER_H_
 
 #include "base/basictypes.h"
+#include "base/export_template_type.h"
 #include "cc/cc_export.h"
 #include "cc/layer_iterator.h"
 #include "cc/region.h"
@@ -13,10 +14,6 @@
 
 namespace cc {
 class OverdrawMetrics;
-class LayerImpl;
-class RenderSurfaceImpl;
-class Layer;
-class RenderSurface;
 
 // This class is used to track occlusion of layers while traversing them in a front-to-back order. As each layer is visited, one of the
 // methods in this class is called to notify it about the current target surface.
@@ -102,6 +99,11 @@ private:
     DISALLOW_COPY_AND_ASSIGN(OcclusionTrackerBase);
 };
 
+EXPORT_TEMPLATE_TYPE(class, CC_EXPORT, Layer);
+EXPORT_TEMPLATE_TYPE(class, CC_EXPORT, LayerImpl);
+EXPORT_TEMPLATE_TYPE(class, CC_EXPORT, RenderSurface);
+EXPORT_TEMPLATE_TYPE(class, CC_EXPORT, RenderSurfaceImpl);
+
 typedef OcclusionTrackerBase<Layer, RenderSurface> OcclusionTracker;
 typedef OcclusionTrackerBase<LayerImpl, RenderSurfaceImpl> OcclusionTrackerImpl;
 #if !defined(COMPILER_MSVC)