callview: improve ui for current and incoming callview

Modify buttons style in incoming and current callview.

Change-Id: I7ee2245596e5587c4aa6072b9117c433241d63a2
diff --git a/pixmaps/ic_high_quality_white_24px.svg b/pixmaps/ic_high_quality_white_24px.svg
new file mode 100644
index 0000000..8b77820
--- /dev/null
+++ b/pixmaps/ic_high_quality_white_24px.svg
@@ -0,0 +1,4 @@
+<svg fill="#ffffff" height="24" viewBox="0 0 24 24" width="24" xmlns="http://www.w3.org/2000/svg">
+    <path d="M0 0h24v24H0z" fill="none"/>
+    <path d="M19 4H5c-1.11 0-2 .9-2 2v12c0 1.1.89 2 2 2h14c1.1 0 2-.9 2-2V6c0-1.1-.9-2-2-2zm-8 11H9.5v-2h-2v2H6V9h1.5v2.5h2V9H11v6zm7-1c0 .55-.45 1-1 1h-.75v1.5h-1.5V15H14c-.55 0-1-.45-1-1v-4c0-.55.45-1 1-1h3c.55 0 1 .45 1 1v4zm-3.5-.5h2v-3h-2v3z"/>
+</svg>