[heap] Allow a minimum semi-space size of 512K.

src/api.cc

Index: src/api.cc
diff --git a/src/api.cc b/src/api.cc
index e920a156a27bc25763262ae17af199ae8df9937c..8871e8f69138e0a518221b3e966096ad30865a18 100644
--- a/src/api.cc
+++ b/src/api.cc
@@ -881,7 +881,7 @@ Extension::Extension(const char* name,
 }
 
 ResourceConstraints::ResourceConstraints()
-    : max_semi_space_size_(0),
+    : max_semi_space_size_in_kb_(0),
       max_old_space_size_(0),
       stack_limit_(NULL),
       code_range_size_(0),
@@ -889,8 +889,8 @@ ResourceConstraints::ResourceConstraints()
 
 void ResourceConstraints::ConfigureDefaults(uint64_t physical_memory,
                                             uint64_t virtual_memory_limit) {
-  set_max_semi_space_size(
-      static_cast<int>(i::Heap::ComputeMaxSemiSpaceSize(physical_memory)));
+  set_max_semi_space_size_in_kb(
+      i::Heap::ComputeMaxSemiSpaceSize(physical_memory));
   set_max_old_space_size(
       static_cast<int>(i::Heap::ComputeMaxOldGenerationSize(physical_memory)));
   set_max_zone_pool_size(i::AccountingAllocator::kMaxPoolSize);
@@ -906,7 +906,7 @@ void ResourceConstraints::ConfigureDefaults(uint64_t physical_memory,
 
 void SetResourceConstraints(i::Isolate* isolate,
                             const ResourceConstraints& constraints) {
-  int semi_space_size = constraints.max_semi_space_size();
+  size_t semi_space_size = constraints.max_semi_space_size_in_kb();
   int old_space_size = constraints.max_old_space_size();
   size_t code_range_size = constraints.code_range_size();
   size_t max_pool_size = constraints.max_zone_pool_size();