Add methods to enable configuration of ResourceConstraints based on limits derived at runtime.

src/platform-solaris.cc

Index: src/platform-solaris.cc
diff --git a/src/platform-solaris.cc b/src/platform-solaris.cc
index df81c3a6bc87fc82042eb45138afeafe570f19d0..6d8140386352219677cde2d6e981ff5466a93703 100644
--- a/src/platform-solaris.cc
+++ b/src/platform-solaris.cc
@@ -173,6 +173,17 @@ void OS::SignalCodeMovingGC() {
 }
 
 
+uintptr_t OS::TotalPhysicalMemory() {
+  intptr_t pages = sysconf(_SC_PHYS_PAGES);
+  intptr_t page_size = sysconf(_SC_PAGESIZE);
+  if (pages == -1 || page_size == -1) {
+    UNREACHABLE();
+    return 0;
+  }
+  return static_cast<uintptr_t>(pages) * page_size;
+}
+
+
 struct StackWalker {
   Vector<OS::StackFrame>& frames;
   int index;