Add code coverage support to android_app JNI libs.

Test: Built mainline module coverage data
Bug: 152117890
Change-Id: I47bf3e5d6e78c4518729bdb52616e248156d3cec

java/java.go

@@ -540,9 +540,10 @@ func (s sdkDep) hasFrameworkLibs() bool {
 }
 
 type jniLib struct {
-	name   string
-	path   android.Path
-	target android.Target
+	name         string
+	path         android.Path
+	target       android.Target
+	coverageFile android.OptionalPath
 }
 
 func (j *Module) shouldInstrument(ctx android.BaseModuleContext) bool {