Remove sdk_version: "core_platform_current"

This (effectively) reverts commit 3c979c33487d7507d2a195291f3cd824ca824b90.

core_platform_current is the new default when no_framework_libs: true
so doesn't need to be specified anywhere.

Bug: 113148576
Test: build
Change-Id: I6bb6c1a0ea24437c8253dc5d8fabd37edabc9d3e
diff --git a/java/java.go b/java/java.go
index 1a73133..0f95479 100644
--- a/java/java.go
+++ b/java/java.go
@@ -434,7 +434,7 @@
 
 func sdkVersionOrDefault(ctx android.BaseContext, v string) string {
 	switch v {
-	case "", "current", "system_current", "test_current", "core_current", "core_platform_current":
+	case "", "current", "system_current", "test_current", "core_current":
 		return ctx.Config().DefaultAppTargetSdk()
 	default:
 		return v
@@ -445,7 +445,7 @@
 // it returns android.FutureApiLevel (10000).
 func sdkVersionToNumber(ctx android.BaseContext, v string) (int, error) {
 	switch v {
-	case "", "current", "test_current", "system_current", "core_current", "core_platform_current":
+	case "", "current", "test_current", "system_current", "core_current":
 		return ctx.Config().DefaultAppTargetSdkInt(), nil
 	default:
 		n := android.GetNumericSdkVersion(v)
@@ -566,8 +566,6 @@
 		return toModule("android_test_stubs_current", "framework-res")
 	case "core_current":
 		return toModule("core.current.stubs", "")
-	case "core_platform_current":
-		return toModule("core.platform.api.stubs", "")
 	default:
 		return toPrebuilt(v)
 	}
@@ -734,7 +732,7 @@
 		name == "stub-annotations" || name == "private-stub-annotations-jar" ||
 		name == "core-lambda-stubs":
 		return javaCore, true
-	case ver == "core_current" || ver == "core_platform_current":
+	case ver == "core_current":
 		return javaCore, false
 	case name == "android_system_stubs_current":
 		return javaSystem, true