sksl support for geometry shaders

BUG=skia:

Change-Id: I8541b98aadcf4c2484fef73e2f49be3ee38bc1e2
Reviewed-on: https://skia-review.googlesource.com/8409
Reviewed-by: Ben Wagner <benjaminwagner@google.com>
Commit-Queue: Ethan Nicholas <ethannicholas@google.com>
diff --git a/src/sksl/SkSLMain.cpp b/src/sksl/SkSLMain.cpp
index f493b05..46e9c18 100644
--- a/src/sksl/SkSLMain.cpp
+++ b/src/sksl/SkSLMain.cpp
@@ -24,8 +24,10 @@
         kind = SkSL::Program::kVertex_Kind;
     } else if (len > 5 && !strcmp(argv[1] + strlen(argv[1]) - 5, ".frag")) {
         kind = SkSL::Program::kFragment_Kind;
+    } else if (len > 5 && !strcmp(argv[1] + strlen(argv[1]) - 5, ".geom")) {
+        kind = SkSL::Program::kGeometry_Kind;
     } else {
-        printf("input filename must end in '.vert' or '.frag'\n");
+        printf("input filename must end in '.vert', '.frag', or '.geom'\n");
         exit(1);
     }