PPC/s390: [builtins] Improve CallApiCallback calling convention.

Port c142e0a2

Original Commit Message:

    Refactor the CallApiCallback builtin to

    - pass the context as with other stubs, and
    - pass holder and call data in registers.

    This avoids having to place holder and call data onto the stack, and
    thus makes it possible to easily call the CallApiCallback builtin from
    other builtins while just forwarding the (stack) arguments. The idea
    is to use this in the future to optimize the general case of calling
    into any API method via a FunctionTemplateInfo and doing appropriate
    security and/or interface checks upfront as necessary (eventually making
    the HandleApiCall C++ builtin obsolete at some point).

R=bmeurer@chromium.org, joransiu@ca.ibm.com, michael_dawson@ca.ibm.com, miladfar@ca.ibm.com
BUG=
LOG=N

Change-Id: I94583d1e0fa7c4696e628c363fefe273c8c5cab9
Reviewed-on: https://chromium-review.googlesource.com/c/1475331Reviewed-by: Milad Farazmand <miladfar@ca.ibm.com>
Commit-Queue: Junliang Yan <jyan@ca.ibm.com>
Cr-Commit-Position: refs/heads/master@{#59633}

src/ppc/interface-descriptors-ppc.cc

@@ -99,6 +99,14 @@ void CallForwardVarargsDescriptor::InitializePlatformSpecific(
   data->InitializePlatformSpecific(arraysize(registers), registers);
 }
 
+void CallFunctionTemplateDescriptor::InitializePlatformSpecific(
+    CallInterfaceDescriptorData* data) {
+  // r4 : function template info
+  // r5 : number of arguments (on the stack, not including receiver)
+  Register registers[] = {r4, r5};
+  data->InitializePlatformSpecific(arraysize(registers), registers);
+}
+
 void CallWithSpreadDescriptor::InitializePlatformSpecific(
     CallInterfaceDescriptorData* data) {
   // r3 : number of arguments (on the stack, not including receiver)

src/s390/interface-descriptors-s390.cc

@@ -98,6 +98,14 @@ void CallForwardVarargsDescriptor::InitializePlatformSpecific(
   data->InitializePlatformSpecific(arraysize(registers), registers);
 }
 
+void CallFunctionTemplateDescriptor::InitializePlatformSpecific(
+    CallInterfaceDescriptorData* data) {
+  // r3 : function template info
+  // r4 : number of arguments (on the stack, not including receiver)
+  Register registers[] = {r3, r4};
+  data->InitializePlatformSpecific(arraysize(registers), registers);
+}
+
 void CallWithSpreadDescriptor::InitializePlatformSpecific(
     CallInterfaceDescriptorData* data) {
   // r2 : number of arguments (on the stack, not including receiver)