Revert "Revert "Remove legacy-test and legacy-android-test targets""

Fixes up the android.test.legacy target to stop using sources directly
now that the issue with android.test.runner-minus-junit not being able
to be built against the SDK has been resolved.

Also, fixes a couple of comments.

This reverts commit 7d7af10dc9.

Reason for revert: When this was originally applied it broke the
pi-dev-plus-aosp branch as it contained references to these targets.
Those references have now been removed.

Bug: 63127064
Change-Id: I619e92faf4cc38f8fd4f053bde832e9a76a2a2bf
Test: make checkbuild

test-base/Android.bp

@@ -44,7 +44,7 @@ java_sdk_library {
 // ==========================================
 // This is only intended for inclusion in the android.test.runner-minus-junit,
 // robolectric_android-all-stub and repackaged.android.test.* libraries.
-// Must not be used elewhere.
+// Must not be used elsewhere.
 java_library_static {
     name: "android.test.base_static",
     installable: false,
@@ -61,19 +61,6 @@ java_library_static {
     sdk_version: "current",
 }
 
-// Build the legacy-test library
-// =============================
-// This contains the junit.framework and android.test classes that were in
-// Android API level 25 excluding those from android.test.runner.
-// Also contains the com.android.internal.util.Predicate[s] classes.
-java_library {
-    name: "legacy-test",
-    installable: true,
-
-    sdk_version: "current",
-    static_libs: ["android.test.base_static"],
-}
-
 // Build the repackaged.android.test.base library
 // ==============================================
 // This contains repackaged versions of the classes from
@@ -93,8 +80,8 @@ java_library_static {
 // ===============================================
 // This contains the android.test classes from android.test.base plus
 // the com.android.internal.util.Predicate[s] classes. This is only
-// intended for inclusion in the android.test.legacy and
-// legacy-android-test static libraries and must not be used elsewhere.
+// intended for inclusion in android.test.legacy and must not be used
+// elsewhere.
 java_library_static {
     name: "android.test.base-minus-junit",