GN: Update heap stubs for android

Source/platform/heap/BUILD.gn

Index: Source/platform/heap/BUILD.gn
diff --git a/Source/platform/heap/BUILD.gn b/Source/platform/heap/BUILD.gn
index c7185bda78f615f3d85f7c774812567639e77c3c..1e4ca86a242f3a5b4a1bd1848ecdd5935d3e6f66 100644
--- a/Source/platform/heap/BUILD.gn
+++ b/Source/platform/heap/BUILD.gn
@@ -16,15 +16,6 @@ source_set("heap") {
     "Visitor.cpp",
     "Visitor.h",
   ]
-  if (cpu_arch == "x86" || cpu_arch == "x64") {

[jamesr, 2014/09/05 01:01:52]

i don't think these did the right thing beforehand.  on intel, the ".asm" file
would be ignored.  On other platforms, the stubs would compile but this target
doesn't set the correct defines for the stubs.  Since there's already a yasm
target in the parent I think the right thing is to just delete this (or move the
whole mess in Source/platform/BUILD.gn up to this directory, or move it to
Source/platform/heap/asm).  WDYT?

-    sources += [ "asm/SaveRegisters_x86.asm" ]
-  } else if (cpu_arch == "arm") {
-    sources += [ "asm/SaveRegisters_arm.S" ]
-  } else if (cpu_arch == "arm64") {
-    sources += [ "asm/SaveRegisters_arm64.S" ]
-  } else if (cpu_arch == "mipsel") {
-    sources += [ "asm/SaveRegisters_mips.S" ]
-  }
 
   configs += [ "//third_party/WebKit/Source:config" ]