Clean up hard-coded Bp/Bn/Bs/IHw prefixes.

Also,
* use iface->localName() instead of "I" + iface->getBaseName()
* do not hardcode IBase related strings
* remove baseName in some places

Bug: 32559427
Test: hidl_test
Change-Id: Ib2049f570ca27d33a945dd6ccb5442e336a11262
diff --git a/Interface.cpp b/Interface.cpp
index 50125d3..4c9e9a5 100644
--- a/Interface.cpp
+++ b/Interface.cpp
@@ -330,16 +330,32 @@
     return fqName().getInterfaceBaseName();
 }
 
+std::string Interface::getProxyName() const {
+    return fqName().getInterfaceProxyName();
+}
+
+std::string Interface::getStubName() const {
+    return fqName().getInterfaceStubName();
+}
+
+std::string Interface::getHwName() const {
+    return fqName().getInterfaceHwName();
+}
+
+std::string Interface::getPassthroughName() const {
+    return fqName().getInterfacePassthroughName();
+}
+
 FQName Interface::getProxyFqName() const {
-    return FQName(fqName().package(), fqName().version(), "Bp" + getBaseName());
+    return fqName().getInterfaceProxyFqName();
 }
 
 FQName Interface::getStubFqName() const {
-    return FQName(fqName().package(), fqName().version(), "Bn" + getBaseName());
+    return fqName().getInterfaceStubFqName();
 }
 
 FQName Interface::getPassthroughFqName() const {
-    return FQName(fqName().package(), fqName().version(), "Bs" + getBaseName());
+    return fqName().getInterfacePassthroughFqName();
 }
 
 std::string Interface::getCppType(StorageMode mode,