libgralloc: Use new GFX API to calculate stride

Use new GFX API compute_aligned_width_and_height to get the stride
value for RGB surfaces.
Backward compatible with GFX old API when old GFX library is used.

Change-Id: I15b0954602b816bf4e88f48622494144fc77c14f
diff --git a/libgralloc/mapper.cpp b/libgralloc/mapper.cpp
index ca0db00..a07bdc3 100644
--- a/libgralloc/mapper.cpp
+++ b/libgralloc/mapper.cpp
@@ -329,7 +329,10 @@
                 int width   = va_arg(args, int);
                 int format  = va_arg(args, int);
                 int *stride = va_arg(args, int *);
-                *stride = AdrenoMemInfo::getInstance().getStride(width, format);
+                int alignedw = 0, alignedh = 0;
+                AdrenoMemInfo::getInstance().getAlignedWidthAndHeight(width,
+                                     0, format, alignedw, alignedh);
+                *stride = alignedw;
                 res = 0;
             } break;
         case GRALLOC_MODULE_PERFORM_GET_CUSTOM_STRIDE_FROM_HANDLE: