Add an NDK ABIs mega build configuration.

The NDK needs generic prebuilts for all architectures.

Test: echo '{ "Ndk_abis": true }' > soong.config && \
          ./soong $OUT_DIR/ndk.timestamp
Bug: None

Change-Id: I2ee3ebbf4cbd1bc593f9e4e9fb44fb66711da9d5

android/arch.go

@@ -799,13 +799,15 @@ func decodeTargetProductVariables(config *config) (map[OsClass][]Target, error)
 	return targets, nil
 }
 
-func decodeMegaDevice() ([]Target, error) {
-	archSettings := []struct {
+type archConfig struct {
 	arch        string
 	archVariant string
 	cpuVariant  string
 	abi         []string
-	}{
+}
+
+func getMegaDeviceConfig() []archConfig {
+	return []archConfig{
 		// armv5 is only used for unbundled apps
 		//{"arm", "armv5te", "", []string{"armeabi"}},
 		{"arm", "armv7-a", "generic", []string{"armeabi-v7a"}},
@@ -846,10 +848,23 @@ func decodeMegaDevice() ([]Target, error) {
 		{"x86_64", "sandybridge", "", []string{"x86_64"}},
 		{"x86_64", "silvermont", "", []string{"x86_64"}},
 	}
+}
 
+func getNdkAbisConfig() []archConfig {
+	return []archConfig{
+		{"arm", "armv5te", "", []string{"armeabi"}},
+		{"arm64", "armv8-a", "", []string{"arm64-v8a"}},
+		{"mips", "mips32-fp", "", []string{"mips"}},
+		{"mips64", "mips64r6", "", []string{"mips64"}},
+		{"x86", "", "", []string{"x86"}},
+		{"x86_64", "", "", []string{"x86_64"}},
+	}
+}
+
+func decodeArchSettings(archConfigs []archConfig) ([]Target, error) {
 	var ret []Target
 
-	for _, config := range archSettings {
+	for _, config := range archConfigs {
 		arch, err := decodeArch(config.arch, &config.archVariant,
 			&config.cpuVariant, &config.abi)
 		if err != nil {

android/config.go

@@ -37,6 +37,7 @@ const productVariablesFileName = "soong.variables"
 // config file. These will be included in the config struct.
 type FileConfigurableOptions struct {
 	Mega_device *bool `json:",omitempty"`
+	Ndk_abis    *bool `json:",omitempty"`
 }
 
 func (f *FileConfigurableOptions) SetDefaultConfig() {
@@ -211,8 +212,15 @@ func NewConfig(srcDir, buildDir string) (Config, error) {
 		return Config{}, err
 	}
 
+	var archConfig []archConfig
 	if Bool(config.Mega_device) {
-		deviceTargets, err := decodeMegaDevice()
+		archConfig = getMegaDeviceConfig()
+	} else if Bool(config.Ndk_abis) {
+		archConfig = getNdkAbisConfig()
+	}
+
+	if archConfig != nil {
+		deviceTargets, err := decodeArchSettings(archConfig)
 		if err != nil {
 			return Config{}, err
 		}