[PT02] Move static methods to ProxyTracker

No logic changes. Only changes are adding nullability annotations,
final modifiers, and adding an s in a comment.

Test: runtests
Change-Id: If4986a25bb36819de8ff459c4c0439c56d4e5a50
diff --git a/services/core/java/com/android/server/ConnectivityService.java b/services/core/java/com/android/server/ConnectivityService.java
index 05b929f..6988720 100644
--- a/services/core/java/com/android/server/ConnectivityService.java
+++ b/services/core/java/com/android/server/ConnectivityService.java
@@ -3309,34 +3309,6 @@
         }
     }
 
-    // Convert empty ProxyInfo's to null as null-checks are used to determine if proxies are present
-    // (e.g. if mGlobalProxy==null fall back to network-specific proxy, if network-specific
-    // proxy is null then there is no proxy in place).
-    private ProxyInfo canonicalizeProxyInfo(ProxyInfo proxy) {
-        if (proxy != null && TextUtils.isEmpty(proxy.getHost())
-                && (proxy.getPacFileUrl() == null || Uri.EMPTY.equals(proxy.getPacFileUrl()))) {
-            proxy = null;
-        }
-        return proxy;
-    }
-
-    // ProxyInfo equality function with a couple modifications over ProxyInfo.equals() to make it
-    // better for determining if a new proxy broadcast is necessary:
-    // 1. Canonicalize empty ProxyInfos to null so an empty proxy compares equal to null so as to
-    //    avoid unnecessary broadcasts.
-    // 2. Make sure all parts of the ProxyInfo's compare true, including the host when a PAC URL
-    //    is in place.  This is important so legacy PAC resolver (see com.android.proxyhandler)
-    //    changes aren't missed.  The legacy PAC resolver pretends to be a simple HTTP proxy but
-    //    actually uses the PAC to resolve; this results in ProxyInfo's with PAC URL, host and port
-    //    all set.
-    private boolean proxyInfoEqual(ProxyInfo a, ProxyInfo b) {
-        a = canonicalizeProxyInfo(a);
-        b = canonicalizeProxyInfo(b);
-        // ProxyInfo.equals() doesn't check hosts when PAC URLs are present, but we need to check
-        // hosts even when PAC URLs are present to account for the legacy PAC resolver.
-        return Objects.equals(a, b) && (a == null || Objects.equals(a.getHost(), b.getHost()));
-    }
-
     public void setGlobalProxy(ProxyInfo proxyProperties) {
         enforceConnectivityInternalPermission();
 
@@ -3470,7 +3442,7 @@
         ProxyInfo newProxyInfo = newLp == null ? null : newLp.getHttpProxy();
         ProxyInfo oldProxyInfo = oldLp == null ? null : oldLp.getHttpProxy();
 
-        if (!proxyInfoEqual(newProxyInfo, oldProxyInfo)) {
+        if (!ProxyTracker.proxyInfoEqual(newProxyInfo, oldProxyInfo)) {
             sendProxyBroadcast(getDefaultProxy());
         }
     }