Fix typos in name of density-independent pixels

Some places referred to "dip" as "device-independent pixels" but it
should be "density-independent pixels." Some publications are starting
to refer to this incorrectly.

Bug: 2586742
Change-Id: I030ef45a5ff61622c95133dcb7f2c82c7df652f0
diff --git a/docs/html/guide/practices/screens_support.jd b/docs/html/guide/practices/screens_support.jd
index 0fad4c6..5e61e6c 100644
--- a/docs/html/guide/practices/screens_support.jd
+++ b/docs/html/guide/practices/screens_support.jd
@@ -116,7 +116,7 @@
 generalized densities: high, medium, and low. Applications can provide custom
 resources for each of these three densities — the platform handles the
 scaling of the resources up or down to meet the actual screen density. </p></dd>
-<dt><em>Density independent pixel (dip)</em></dt>
+<dt><em>Density-independent pixel (dip)</em></dt>
   <dd>A virtual pixel unit that applications can use in defining their UI, to
 express layout dimensions or position in a density-independent way. 
   <p>The density-independent pixel is equivalent to one physical pixel on a 160
@@ -432,7 +432,7 @@
 <ul>
 <li>Through pre-scaling of drawable resources (scaled at resource loading
 time)</li>
-<li>Through auto-scaling of device-independent pixel (dip) values used in
+<li>Through auto-scaling of density-independent pixel (dip) values used in
 layouts</li>
 <li>Through auto-scaling of absolute pixel values used in the application (only
 needed if the application has set <code>android:anyDensity="false"</code> in its
@@ -573,7 +573,7 @@
 are signaling to the platform that your application wants to manage its UI by
 itself, for all screen densities, using the actual screen dimensions and pixels.
 In this case, the application must ensure that it declares its UI dimensions
-using device-independent pixels and scales any actual pixel values or math by
+using density-independent pixels and scales any actual pixel values or math by
 the scaling factor available from 
 {@link android.util.DisplayMetrics#density android.util.DisplayMetrics.density}.</p>