refactor Bazel variable export

Most of the variable export code for cc modules can be re-used for
exporting variables for java modules. Refactor this code into a more
composable structure for reuse.

Test: build/bazel/bp2build.sh
Test: manual comparison of
  out/soong/soong_injection/cc_toolchain/constants.bzl
  with previous output
Change-Id: Ie5a6fee08cc888b7dc69c3e324e5c3f8aa269a8f
diff --git a/cc/config/arm64_device.go b/cc/config/arm64_device.go
index 4d0ae1a..dfe143f 100644
--- a/cc/config/arm64_device.go
+++ b/cc/config/arm64_device.go
@@ -98,28 +98,28 @@
 	pctx.SourcePathVariable("Arm64GccRoot",
 		"prebuilts/gcc/${HostPrebuiltTag}/aarch64/aarch64-linux-android-${arm64GccVersion}")
 
-	exportStringListStaticVariable("Arm64Ldflags", arm64Ldflags)
-	exportStringListStaticVariable("Arm64Lldflags", arm64Lldflags)
+	exportedVars.ExportStringListStaticVariable("Arm64Ldflags", arm64Ldflags)
+	exportedVars.ExportStringListStaticVariable("Arm64Lldflags", arm64Lldflags)
 
-	exportStringListStaticVariable("Arm64Cflags", arm64Cflags)
-	exportStringListStaticVariable("Arm64Cppflags", arm64Cppflags)
+	exportedVars.ExportStringListStaticVariable("Arm64Cflags", arm64Cflags)
+	exportedVars.ExportStringListStaticVariable("Arm64Cppflags", arm64Cppflags)
 
-	exportedVariableReferenceDictVars.Set("Arm64ArchVariantCflags", arm64ArchVariantCflagsVar)
-	exportedVariableReferenceDictVars.Set("Arm64CpuVariantCflags", arm64CpuVariantCflagsVar)
-	exportedVariableReferenceDictVars.Set("Arm64CpuVariantLdflags", arm64CpuVariantLdflags)
+	exportedVars.ExportVariableReferenceDict("Arm64ArchVariantCflags", arm64ArchVariantCflagsVar)
+	exportedVars.ExportVariableReferenceDict("Arm64CpuVariantCflags", arm64CpuVariantCflagsVar)
+	exportedVars.ExportVariableReferenceDict("Arm64CpuVariantLdflags", arm64CpuVariantLdflags)
 
-	exportStringListStaticVariable("Arm64Armv8ACflags", arm64ArchVariantCflags["armv8-a"])
-	exportStringListStaticVariable("Arm64Armv8ABranchProtCflags", arm64ArchVariantCflags["armv8-a-branchprot"])
-	exportStringListStaticVariable("Arm64Armv82ACflags", arm64ArchVariantCflags["armv8-2a"])
-	exportStringListStaticVariable("Arm64Armv82ADotprodCflags", arm64ArchVariantCflags["armv8-2a-dotprod"])
+	exportedVars.ExportStringListStaticVariable("Arm64Armv8ACflags", arm64ArchVariantCflags["armv8-a"])
+	exportedVars.ExportStringListStaticVariable("Arm64Armv8ABranchProtCflags", arm64ArchVariantCflags["armv8-a-branchprot"])
+	exportedVars.ExportStringListStaticVariable("Arm64Armv82ACflags", arm64ArchVariantCflags["armv8-2a"])
+	exportedVars.ExportStringListStaticVariable("Arm64Armv82ADotprodCflags", arm64ArchVariantCflags["armv8-2a-dotprod"])
 
-	exportStringListStaticVariable("Arm64CortexA53Cflags", arm64CpuVariantCflags["cortex-a53"])
-	exportStringListStaticVariable("Arm64CortexA55Cflags", arm64CpuVariantCflags["cortex-a55"])
-	exportStringListStaticVariable("Arm64KryoCflags", arm64CpuVariantCflags["kryo"])
-	exportStringListStaticVariable("Arm64ExynosM1Cflags", arm64CpuVariantCflags["exynos-m1"])
-	exportStringListStaticVariable("Arm64ExynosM2Cflags", arm64CpuVariantCflags["exynos-m2"])
+	exportedVars.ExportStringListStaticVariable("Arm64CortexA53Cflags", arm64CpuVariantCflags["cortex-a53"])
+	exportedVars.ExportStringListStaticVariable("Arm64CortexA55Cflags", arm64CpuVariantCflags["cortex-a55"])
+	exportedVars.ExportStringListStaticVariable("Arm64KryoCflags", arm64CpuVariantCflags["kryo"])
+	exportedVars.ExportStringListStaticVariable("Arm64ExynosM1Cflags", arm64CpuVariantCflags["exynos-m1"])
+	exportedVars.ExportStringListStaticVariable("Arm64ExynosM2Cflags", arm64CpuVariantCflags["exynos-m2"])
 
-	exportStringListStaticVariable("Arm64FixCortexA53Ldflags", []string{"-Wl,--fix-cortex-a53-843419"})
+	exportedVars.ExportStringListStaticVariable("Arm64FixCortexA53Ldflags", []string{"-Wl,--fix-cortex-a53-843419"})
 }
 
 var (