Add support for a target new space size

src/heap/spaces.h

Index: src/heap/spaces.h
diff --git a/src/heap/spaces.h b/src/heap/spaces.h
index ef55357163924af08705b59366101e4747069b46..5be9c3a11fdfbe4d7659786217ff74dd83304bd0 100644
--- a/src/heap/spaces.h
+++ b/src/heap/spaces.h
@@ -2075,7 +2075,8 @@ class SemiSpace : public Space {
         current_page_(NULL) {}
 
   // Sets up the semispace using the given chunk.
-  void SetUp(Address start, int initial_capacity, int maximum_capacity);
+  void SetUp(Address start, int initial_capacity, int target_capacity,
+             int maximum_capacity);
 
   // Tear down the space.  Heap memory was not allocated by the space, so it
   // is not deallocated here.
@@ -2094,6 +2095,9 @@ class SemiSpace : public Space {
   // semispace and less than the current capacity.
   bool ShrinkTo(int new_capacity);
 
+  // Sets the total capacity. Only possible when the space is not committed.
+  bool SetTotalCapacity(int new_capacity);
+
   // Returns the start address of the first page of the space.
   Address space_start() {
     DCHECK(anchor_.next_page() != &anchor_);
@@ -2168,6 +2172,9 @@ class SemiSpace : public Space {
   // Returns the current total capacity of the semispace.
   int TotalCapacity() { return total_capacity_; }
 
+  // Returns the target for total capacity of the semispace.
+  int TargetCapacity() { return target_capacity_; }
+
   // Returns the maximum total capacity of the semispace.
   int MaximumTotalCapacity() { return maximum_total_capacity_; }
 
@@ -2196,6 +2203,7 @@ class SemiSpace : public Space {
 
   // The current and maximum total capacity of the space.
   int total_capacity_;
+  int target_capacity_;
   int maximum_total_capacity_;
   int initial_total_capacity_;
 
@@ -2341,6 +2349,9 @@ class NewSpace : public Space {
   // their maximum capacity.
   void Grow();
 
+  // Grow the capacity of the semispaces by one page.
+  bool GrowOnePage();
+
   // Shrink the capacity of the semispaces.
   void Shrink();