soong: Support system_server jars from apexes

Allow system_server jars delivered via apex. Regular system_server
jars are located in /system/framework folder. But, jars delivered via
apex are mounted at /apex/<module_name>/javalib.

Bug: 144722612
Bug: 141785760
Test: Compiles
Change-Id: Ia40bb91d2e05b2601a52eac28a985fe2d8da3481

dexpreopt/config.go

@@ -44,9 +44,10 @@ type GlobalConfig struct {
 	ProductUpdatableBootModules   []string
 	ProductUpdatableBootLocations []string
 
-	SystemServerJars []string // jars that form the system server
-	SystemServerApps []string // apps that are loaded into system server
-	SpeedApps        []string // apps that should be speed optimized
+	SystemServerJars          []string // jars that form the system server
+	SystemServerApps          []string // apps that are loaded into system server
+	UpdatableSystemServerJars []string // jars within apex that are loaded into system server
+	SpeedApps                 []string // apps that should be speed optimized
 
 	PreoptFlags []string // global dex2oat flags that should be used if no module-specific dex2oat flags are specified
 
@@ -285,6 +286,7 @@ func GlobalConfigForTests(ctx android.PathContext) GlobalConfig {
 		ProductUpdatableBootLocations:      nil,
 		SystemServerJars:                   nil,
 		SystemServerApps:                   nil,
+		UpdatableSystemServerJars:          nil,
 		SpeedApps:                          nil,
 		PreoptFlags:                        nil,
 		DefaultCompilerFilter:              "",

java/dexpreopt_config.go

@@ -15,6 +15,7 @@
 package java
 
 import (
+	"fmt"
 	"path/filepath"
 	"strings"
 
@@ -65,6 +66,16 @@ func setDexpreoptTestGlobalConfig(config android.Config, globalConfig dexpreopt.
 var dexpreoptGlobalConfigKey = android.NewOnceKey("DexpreoptGlobalConfig")
 var dexpreoptTestGlobalConfigKey = android.NewOnceKey("TestDexpreoptGlobalConfig")
 
+// Expected format for apexJarValue = <apex name>:<jar name>
+func splitApexJarPair(apexJarValue string) (string, string)  {
+	var apexJarPair []string = strings.SplitN(apexJarValue, ":", 2)
+	if apexJarPair == nil || len(apexJarPair) != 2 {
+		panic(fmt.Errorf("malformed apexJarValue: %q, expected format: <apex>:<jar>",
+			apexJarValue))
+	}
+	return apexJarPair[0], apexJarPair[1]
+}
+
 // systemServerClasspath returns the on-device locations of the modules in the system server classpath.  It is computed
 // once the first time it is called for any ctx.Config(), and returns the same slice for all future calls with the same
 // ctx.Config().
@@ -77,6 +88,11 @@ func systemServerClasspath(ctx android.PathContext) []string {
 			systemServerClasspathLocations = append(systemServerClasspathLocations,
 				filepath.Join("/system/framework", m+".jar"))
 		}
+		for _, m := range global.UpdatableSystemServerJars {
+			apex, jar := splitApexJarPair(m)
+			systemServerClasspathLocations = append(systemServerClasspathLocations,
+				filepath.Join("/apex", apex, "javalib", jar + ".jar"))
+		}
 		return systemServerClasspathLocations
 	})
 }