[移除 Toolbar 左侧空白. Remove left margin from actionbars custom layout.] https://stackoverflow.com/a/32320632/2722270
#tags: android-view
<android.support.v7.widget.Toolbar
xmlns:app="schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="@color/primaryColor"
android:contentInsetLeft="0dp"
android:contentInsetStart="0dp"
app:contentInsetLeft="0dp"
app:contentInsetStart="0dp"
android:contentInsetRight="0dp"
android:contentInsetEnd="0dp"
app:contentInsetRight="0dp"
app:contentInsetEnd="0dp" />