Add new camera focus mode FOCUS_MODE_CONTINUOUS_PICTURE.

The API is still hidden.

bug:5086125
Change-Id: I69268a95ad6aae249771d3a8dfb423ffe2d87081
diff --git a/libs/camera/CameraParameters.cpp b/libs/camera/CameraParameters.cpp
index 51b96c1..0eb5d50 100644
--- a/libs/camera/CameraParameters.cpp
+++ b/libs/camera/CameraParameters.cpp
@@ -160,6 +160,7 @@
 const char CameraParameters::FOCUS_MODE_FIXED[] = "fixed";
 const char CameraParameters::FOCUS_MODE_EDOF[] = "edof";
 const char CameraParameters::FOCUS_MODE_CONTINUOUS_VIDEO[] = "continuous-video";
+const char CameraParameters::FOCUS_MODE_CONTINUOUS_PICTURE[] = "continuous-picture";
 
 CameraParameters::CameraParameters()
                 : mMap()