Update package path for Java.

We used to put IFoo.java with package android.hardware.foo.V1_0
under android/hardware/foo/1.0; the last element is fixed to
V1_0.

Test: compiles
Test: hidl_test_java

Bug: 33554192
Change-Id: I6a6a7d6c0a4c95e7c0797643bc98bec5c12889ca
diff --git a/FQName.cpp b/FQName.cpp
index 02e31e2..700af9f 100644
--- a/FQName.cpp
+++ b/FQName.cpp
@@ -175,6 +175,14 @@
     return mMajor + "." + mMinor;
 }
 
+std::string FQName::sanitizedVersion() const {
+    CHECK(mMajor.empty() == mMinor.empty());
+    if (mMajor.empty() && mMinor.empty()) {
+        return "";
+    }
+    return "V" + mMajor + "_" + mMinor;
+}
+
 std::string FQName::atVersion() const {
     std::string v = version();
     return v.empty() ? "" : ("@" + v);
@@ -368,13 +376,7 @@
         return;
     }
 
-    // Form "Vmajor_minor".
-    std::string versionString = "V";
-    versionString.append(getPackageMajorVersion());
-    versionString.append("_");
-    versionString.append(getPackageMinorVersion());
-
-    components->push_back(versionString);
+    components->push_back(sanitizedVersion());
 }
 
 std::string FQName::getPackageMajorVersion() const {