[Android] Stop using org.apache.http classes in AccessibilityInjector.

As part of the efforts to stop depending on external packages in the
code, replace usage of org.apache.http classes with an implementation
that only uses apache.net.Uri.

This allows us to drop the dependency on the legacy_http_client target
and end up having to bundle org.apache.http.legacy.jar into
xwalk_core_library.jar.

Not upstreamable, as the code in question was removed upstream when they
dropped support for ICS.

BUG=XWALK-5092

content/content.gyp

@@ -600,7 +600,6 @@
           'dependencies': [
             'java_set_jni_headers',
             'motionevent_jni_headers',
-            '../third_party/android_tools/android_tools.gyp:legacy_http_javalib',
           ],
           'includes': [ 'content_jni.gypi' ],
         },

content/public/android/java/src/org/chromium/content/browser/accessibility/AccessibilityInjector.java

@@ -7,6 +7,7 @@
 import android.accessibilityservice.AccessibilityServiceInfo;
 import android.content.Context;
 import android.content.pm.PackageManager;
+import android.net.Uri;
 import android.os.Build;
 import android.os.Bundle;
 import android.os.Vibrator;
@@ -15,17 +16,13 @@
 import android.view.accessibility.AccessibilityManager;
 import android.view.accessibility.AccessibilityNodeInfo;
 
-import org.apache.http.NameValuePair;
-import org.apache.http.client.utils.URLEncodedUtils;
 import org.chromium.base.CommandLine;
 import org.chromium.content.browser.ContentViewCore;
 import org.chromium.content.browser.JavascriptInterface;
 import org.chromium.content.common.ContentSwitches;
 import org.json.JSONException;
 import org.json.JSONObject;
 
-import java.net.URI;
-import java.net.URISyntaxException;
 import java.util.HashMap;
 import java.util.Iterator;
 import java.util.List;
@@ -305,16 +302,11 @@ private int getAxsUrlParameterValue() {
         }
 
         try {
-            List<NameValuePair> params = URLEncodedUtils.parse(
-                    new URI(mContentViewCore.getWebContents().getUrl()), null);
-
-            for (NameValuePair param : params) {
-                if ("axs".equals(param.getName())) {
-                    return Integer.parseInt(param.getValue());
-                }
+            Uri uri = Uri.parse(mContentViewCore.getWebContents().getUrl());
+            String axs = uri.getQueryParameter("axs");
+            if (axs != null) {
+                return Integer.parseInt(axs);
             }
-        } catch (URISyntaxException ex) {
-            // Intentional no-op.
         } catch (NumberFormatException ex) {
             // Intentional no-op.
         } catch (IllegalArgumentException ex) {