Support use of custom fonts in miniui

Bug: 29547343
Change-Id: I398160c85daac90ffab2fa9bb2e96795b9e9885a
diff --git a/minui/font_10x18.h b/minui/font_10x18.h
index 29d7053..30dfb9c 100644
--- a/minui/font_10x18.h
+++ b/minui/font_10x18.h
@@ -1,14 +1,14 @@
 struct {
   unsigned width;
   unsigned height;
-  unsigned cwidth;
-  unsigned cheight;
+  unsigned char_width;
+  unsigned char_height;
   unsigned char rundata[2973];
 } font = {
   .width = 960,
   .height = 18,
-  .cwidth = 10,
-  .cheight = 18,
+  .char_width = 10,
+  .char_height = 18,
   .rundata = {
 0x7f,0x7f,0x7f,0x7f,0x7f,0x7f,0x7f,0x55,0x82,0x06,0x82,0x02,0x82,0x10,0x82,
 0x11,0x83,0x08,0x82,0x0a,0x82,0x04,0x82,0x46,0x82,0x08,0x82,0x07,0x84,0x06,