Add contact photo for missed call notifications

+ ContactPhotoLoader to create the appropriate icon from a ContactInfo
- NameLookupQuery in CallLogNotificationsHelper#getContactInfo
  To show a photo the name is not enough. Full query need to be made to
  retrieve the photoUri.
+ class Assert in util
+ Gradle directory setup for dialer tests
  (Note: this is just for project setup in Android Studio, tests are
  still not runnable in gradle)

Bug:27276108
Change-Id: I0ed2147f2bb60454fe5a5ad6c25fe99727441880
diff --git a/build-app.gradle b/build-app.gradle
index 9e24136..2ea4376 100644
--- a/build-app.gradle
+++ b/build-app.gradle
@@ -12,6 +12,11 @@
         manifest.srcFile 'AndroidManifest.xml'
         res.srcDirs = ['res']
     }
+
+    sourceSets.androidTest {
+        java.srcDirs = ['tests/src']
+        res.srcDirs = ['test/res']
+    }
 }
 
 dependencies {