1) created a new build flavor for espresso tests

2) create a new source set full of espresso tests
3) updated proguard-testing.pro
4) added test device numbers to .gitignore

// FREEBIE

test/androidTestEspresso/java/org/thoughtcrime/securesms/ViewMatchers.java

@@ -0,0 +1,72 @@
+/**
+ * Copyright (C) 2015 Open Whisper Systems
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package org.thoughtcrime.securesms;
+
+import android.support.v7.widget.RecyclerView;
+import android.view.View;
+
+import org.hamcrest.Description;
+import org.hamcrest.Matcher;
+import org.hamcrest.TypeSafeMatcher;
+
+public class ViewMatchers {
+
+  public static Matcher<View> withRecyclerItem(final Matcher<Object> itemMatcher) {
+    return new TypeSafeMatcher<View>() {
+      @Override
+      public void describeTo(Description description) {
+        description.appendText("with recycler item: ");
+        itemMatcher.describeTo(description);
+      }
+
+      @Override
+      public boolean matchesSafely(View view) {
+        if (!(view instanceof RecyclerView)) {
+          return false;
+        }
+
+        RecyclerView recyclerView = ((RecyclerView) view);
+        for (int i = 0; i < recyclerView.getChildCount(); i++) {
+          if (itemMatcher.matches(recyclerView.getChildAt(i))) {
+            return true;
+          }
+        }
+        return false;
+      }
+    };
+  }
+
+  public static Matcher<View> withRecyclerItemCount(final long itemCount) {
+    return new TypeSafeMatcher<View>() {
+      @Override
+      public void describeTo(Description description) {
+        description.appendText("with recycler item count: " + itemCount);
+      }
+
+      @Override
+      public boolean matchesSafely(View view) {
+        if (!(view instanceof RecyclerView)) {
+          return false;
+        }
+
+        RecyclerView recyclerView = ((RecyclerView) view);
+        return recyclerView.getChildCount() == itemCount;
+      }
+    };
+  }
+
+}