Intrinsify fixed and growable array allocation on x64.

runtime/vm/intrinsifier_ia32.cc

Index: runtime/vm/intrinsifier_ia32.cc
===================================================================
--- runtime/vm/intrinsifier_ia32.cc	(revision 9070)
+++ runtime/vm/intrinsifier_ia32.cc	(working copy)
@@ -36,7 +36,7 @@
   Label fall_through;
 
   // Compute the size to be allocated, it is based on the array length
-  // and it computed as:
+  // and is computed as:
   // RoundedAllocationSize((array_length * kwordSize) + sizeof(RawArray)).
   __ movl(EDI, Address(ESP, kArrayLengthOffset));  // Array Length.
   // Assert that length is a Smi.
@@ -262,7 +262,7 @@
   Label fall_through;
 
   // Compute the size to be allocated, it is based on the array length
-  // and it computed as:
+  // and is computed as:
   // RoundedAllocationSize(sizeof(RawGrowableObjectArray)) +
   intptr_t fixed_size = GrowableObjectArray::InstanceSize();