Android: Minor simplification to conditionals in abi.gni

No behaviour change

Change-Id: I457a35b215c545a5049b67739607aa5b331ca301
Reviewed-on: https://chromium-review.googlesource.com/c/1455115
Commit-Queue: Christopher Grant <cjgrant@chromium.org>
Auto-Submit: Andrew Grieve <agrieve@chromium.org>
Reviewed-by: Christopher Grant <cjgrant@chromium.org>
Cr-Commit-Position: refs/heads/master@{#629595}

build/config/android/abi.gni

@@ -44,37 +44,23 @@ if (current_cpu == "x86") {
   android_app_abi = "mips"
 } else if (current_cpu == "x64") {
   android_app_abi = "x86_64"
+  android_secondary_abi_cpu = "x86"
+  android_app_secondary_abi = "x86"
 } else if (current_cpu == "arm64") {
   android_app_abi = "arm64-v8a"
+  android_secondary_abi_cpu = "arm"
+  android_app_secondary_abi = "armeabi-v7a"
 } else if (current_cpu == "mips64el") {
   android_app_abi = "mips64"
+  android_secondary_abi_cpu = "mipsel"
+  android_app_secondary_abi = "mips"
 } else {
   assert(false, "Unknown Android ABI: " + current_cpu)
 }
 
-if (target_cpu == "arm64" || target_cpu == "x64" || target_cpu == "mips64el") {
-  android_64bit_target_cpu = true
-} else if (target_cpu == "arm" || target_cpu == "x86" ||
-           target_cpu == "mipsel") {
-  android_64bit_target_cpu = false
-} else {
-  assert(false, "Unknown target CPU: $target_cpu")
-}
-
-# Intentionally do not define android_app_secondary_abi_cpu and
-# android_app_secondary_abi for 32-bit target_cpu, since they are not used.
-if (target_cpu == "arm64") {
-  android_secondary_abi_cpu = "arm"
-  android_app_secondary_abi = "armeabi-v7a"
-} else if (target_cpu == "x64") {
-  android_secondary_abi_cpu = "x86"
-  android_app_secondary_abi = "x86"
-} else if (target_cpu == "mips64el") {
-  android_secondary_abi_cpu = "mipsel"
-  android_app_secondary_abi = "mips"
-}
+android_64bit_target_cpu = defined(android_app_secondary_abi)
 
-if (defined(android_secondary_abi_cpu)) {
+if (android_64bit_target_cpu) {
   android_secondary_abi_toolchain =
       "//build/toolchain/android:android_clang_${android_secondary_abi_cpu}"
 }