remove explicit 'f' in glbench shader

bench/GLInstancedArraysBench.cpp

Index: bench/GLInstancedArraysBench.cpp
diff --git a/bench/GLInstancedArraysBench.cpp b/bench/GLInstancedArraysBench.cpp
index 4ef813c852d36fee0871ba6aa5d0b054c262fcd9..d89c0876052b952a3fa662cfc74b81ad05986f28 100644
--- a/bench/GLInstancedArraysBench.cpp
+++ b/bench/GLInstancedArraysBench.cpp
@@ -126,7 +126,7 @@ GrGLuint GLCpuPosInstancedArraysBench::setupShader(const GrGLContext* ctx) {
     vshaderTxt.append(
             "void main()\n"
             "{\n"
-                "gl_Position = vec4(a_position, 0.f, 1.f);\n"
+                "gl_Position = vec4(a_position, 0., 1.);\n"
                 "o_color = a_color;\n"
             "}\n");
 
@@ -152,7 +152,7 @@ GrGLuint GLCpuPosInstancedArraysBench::setupShader(const GrGLContext* ctx) {
     fshaderTxt.appendf(
             "void main()\n"
             "{\n"
-                "%s = vec4(o_color, 1.0f);\n"
+                "%s = vec4(o_color, 1.0);\n"
             "}\n", fsOutName);
 
     return CreateProgram(gl, vshaderTxt.c_str(), fshaderTxt.c_str());