Reland "Turn libbase into a component"

src/base/sys-info.h

Index: src/base/sys-info.h
diff --git a/src/base/sys-info.h b/src/base/sys-info.h
index 4504c82e37ef21f9497d394f31e4ae40c426bc51..772f44336f0d84aa34e5e973e88d592bbc7bd813 100644
--- a/src/base/sys-info.h
+++ b/src/base/sys-info.h
@@ -6,12 +6,14 @@
 #define V8_BASE_SYS_INFO_H_
 
 #include <stdint.h>
+
+#include "src/base/base-export.h"
 #include "src/base/compiler-specific.h"
 
 namespace v8 {
 namespace base {
 
-class SysInfo final {
+class V8_BASE_EXPORT SysInfo final {
  public:
   // Returns the number of logical processors/core on the current machine.
   static int NumberOfProcessors();