ES31: Add glGetProgramResourceIndex API

Add API entry and validation checks(GLES 3.1 section 7.3).
Add the first 2 interfaces(PROGRAM_INPUT and PROGRAM_OUTPUT) implementation.

BUG=angleproject:1920

Change-Id: Ib2dedded9fd79b315e9f38de7c27a5e4ec4c6066
Reviewed-on: https://chromium-review.googlesource.com/453085
Commit-Queue: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
diff --git a/src/common/utilities.cpp b/src/common/utilities.cpp
index e3dec3e..b03aada 100644
--- a/src/common/utilities.cpp
+++ b/src/common/utilities.cpp
@@ -697,7 +697,7 @@
     }
 }
 
-std::string ParseUniformName(const std::string &name, size_t *outSubscript)
+std::string ParseResourceName(const std::string &name, size_t *outSubscript)
 {
     // Strip any trailing array operator and retrieve the subscript
     size_t open = name.find_last_of('[');