Fix tests to use correct fixtures for configuring (Apex)BootJars.

This is in preparation to r.android.com/1740313 where setting correct
variables would be enforced (i.e. apex and non-apex boot jars must be in
config.ApexBootJars and config.BootJars correspondingly).

Bug: 191369843
Test: m nothing
Change-Id: Ic86680c1f7af53d229083b2cc58beb3ceccb4b6a
diff --git a/apex/classpath_element_test.go b/apex/classpath_element_test.go
index 0193127..e2d8465 100644
--- a/apex/classpath_element_test.go
+++ b/apex/classpath_element_test.go
@@ -58,6 +58,7 @@
 		}),
 		java.PrepareForTestWithJavaSdkLibraryFiles,
 		java.FixtureWithLastReleaseApis("foo", "othersdklibrary"),
+		java.FixtureConfigureApexBootJars("myapex:bar"),
 		android.FixtureWithRootAndroidBp(`
 		apex {
 			name: "com.android.art",
@@ -79,6 +80,7 @@
 
 		bootclasspath_fragment {
 			name: "art-bootclasspath-fragment",
+			image_name: "art",
 			apex_available: [
 				"com.android.art",
 			],
@@ -193,6 +195,10 @@
 					apex: "com.android.art",
 					module: "art-bootclasspath-fragment",
 				},
+				{
+					apex: "myapex",
+					module: "mybootclasspath-fragment",
+				},
 			],
 		}
 	`),