Rename UpdatableSystemServerJars to ApexSystemServerJars.

This is consistent with naming for boot jars, e.g. ApexBootJars.

Bug: 191127295
Test: presubmit
Change-Id: I6e8828d55ac86b7f5260ed7f8d4eca1c0b3dced8
diff --git a/dexpreopt/config.go b/dexpreopt/config.go
index d4ab4bc..7a74506 100644
--- a/dexpreopt/config.go
+++ b/dexpreopt/config.go
@@ -49,10 +49,10 @@
 
 	ArtApexJars android.ConfiguredJarList // modules for jars that are in the ART APEX
 
-	SystemServerJars          android.ConfiguredJarList // jars that form the system server
-	SystemServerApps          []string                  // apps that are loaded into system server
-	UpdatableSystemServerJars android.ConfiguredJarList // jars within apex that are loaded into system server
-	SpeedApps                 []string                  // apps that should be speed optimized
+	SystemServerJars     android.ConfiguredJarList // jars that form the system server
+	SystemServerApps     []string                  // apps that are loaded into system server
+	ApexSystemServerJars android.ConfiguredJarList // jars within apex that are loaded into system server
+	SpeedApps            []string                  // apps that should be speed optimized
 
 	BrokenSuboptimalOrderOfSystemServerJars bool // if true, sub-optimal order does not cause a build error
 
@@ -618,7 +618,7 @@
 		ArtApexJars:                        android.EmptyConfiguredJarList(),
 		SystemServerJars:                   android.EmptyConfiguredJarList(),
 		SystemServerApps:                   nil,
-		UpdatableSystemServerJars:          android.EmptyConfiguredJarList(),
+		ApexSystemServerJars:               android.EmptyConfiguredJarList(),
 		SpeedApps:                          nil,
 		PreoptFlags:                        nil,
 		DefaultCompilerFilter:              "",