Add Field Trial factor to NewTabPageLayout calculations.

chrome/android/java/src/org/chromium/chrome/browser/ntp/cards/CardsFieldTrial.java

Index: chrome/android/java/src/org/chromium/chrome/browser/ntp/cards/CardsFieldTrial.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/ntp/cards/CardsFieldTrial.java b/chrome/android/java/src/org/chromium/chrome/browser/ntp/cards/CardsFieldTrial.java
new file mode 100644
index 0000000000000000000000000000000000000000..96dcd7a0f65a002054a14cd1a2b3f2c1b7626ad7
--- /dev/null
+++ b/chrome/android/java/src/org/chromium/chrome/browser/ntp/cards/CardsFieldTrial.java
@@ -0,0 +1,48 @@
+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.chrome.browser.ntp.cards;
+
+import android.text.TextUtils;
+
+import org.chromium.base.CommandLine;
+import org.chromium.base.Log;
+import org.chromium.chrome.browser.ntp.NewTabPage;
+import org.chromium.components.variations.VariationsAssociatedData;
+
+/**
+ * Provides easy access to data for field trials to do with the Cards UI.
+ */
+public final class CardsFieldTrial {
+    private static final String TAG = "CardFinchExperiments";
+
+    // TODO(peconn): Move NewTabPage.FIELD_TRIAL_NAME and all uses into this class.
+    private static final String FIRST_CARD_OFFSET = "first_card_offset";
+
+    private CardsFieldTrial() {
+    }
+
+    /**
+     * Provides the value of the field trial to offset the peeking card (can be overridden
+     * with a command line flag). It will return 0 if there is no such field trial.
+     */
+    public static int getFirstCardOffsetDp() {
+        String value = CommandLine.getInstance().getSwitchValue(FIRST_CARD_OFFSET);
+
+        if (TextUtils.isEmpty(value)) {
+            value = VariationsAssociatedData.getVariationParamValue(NewTabPage.FIELD_TRIAL_NAME,
+                    FIRST_CARD_OFFSET);
+        }
+
+        if (!TextUtils.isEmpty(value)) {
+            try {
+                return Integer.parseInt(value);
+            } catch (NumberFormatException ex) {
+                Log.w(TAG, "Cannot parse card offset experiment value, %s.", value);
+            }
+        }
+
+        return 0;
+    }
+}