PPC/s390: MIPS[64] Fix SizeOfInitialHeap test failing

Port 316254a7

Original Commit Message:

    Commit 0d833cb9 deleted function call
    that created CEntryStub code in snapshot. So when CEntryStub::GetCode is
    called while initializing V8, the code for it, is not found in shapshot.
    Hence this code has to be generated in new allocation on heap, that is
    why initial heap is above the limit.
    This patch assures that CEntryStub code is in the snapshot.

R=predrag.rudic@imgtec.com, joransiu@ca.ibm.com, jyan@ca.ibm.com, michael_dawson@ca.ibm.com
BUG=
LOG=N

Change-Id: I976dacf885e0d4ce8c5446a2c560a00cc0792150
Reviewed-on: https://chromium-review.googlesource.com/596071Reviewed-by: Junliang Yan <jyan@ca.ibm.com>
Commit-Queue: Jaideep Bajwa <bjaideep@ca.ibm.com>
Cr-Commit-Position: refs/heads/master@{#47054}

src/ppc/code-stubs-ppc.cc

@@ -846,6 +846,8 @@ void CodeStub::GenerateFPStubs(Isolate* isolate) {
 void CEntryStub::GenerateAheadOfTime(Isolate* isolate) {
   CEntryStub stub(isolate, 1, kDontSaveFPRegs);
   stub.GetCode();
+  CEntryStub save_doubles(isolate, 1, kSaveFPRegs);
+  save_doubles.GetCode();
 }
 
 

src/s390/code-stubs-s390.cc

@@ -805,6 +805,8 @@ void CodeStub::GenerateFPStubs(Isolate* isolate) {
 void CEntryStub::GenerateAheadOfTime(Isolate* isolate) {
   CEntryStub stub(isolate, 1, kDontSaveFPRegs);
   stub.GetCode();
+  CEntryStub save_doubles(isolate, 1, kSaveFPRegs);
+  save_doubles.GetCode();
 }
 
 void CEntryStub::Generate(MacroAssembler* masm) {