Refactor ANGLE Extensions Validation

Refactors ANGLE Extensions Validation functions into a common format for
future autogeneration. Any writes to output parameters that occurred
within the ANGLE entry point have been moved into the corresponding
validation function.

Bug:angleproject:2263
Change-Id: I7a678310ad481c1379596a493fcb0b0383fcf3b8
Reviewed-on: https://chromium-review.googlesource.com/985244
Commit-Queue: Brandon1 Jones <brandon1.jones@intel.com>
Commit-Queue: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Jamie Madill <jmadill@chromium.org>
diff --git a/src/libANGLE/validationES2.cpp b/src/libANGLE/validationES2.cpp
index ab448a6..3d3c593 100644
--- a/src/libANGLE/validationES2.cpp
+++ b/src/libANGLE/validationES2.cpp
@@ -3483,6 +3483,16 @@
     return true;
 }
 
+bool ValidateCoverFillPathCHROMIUM(Context *context, GLuint path, GLenum coverMode)
+{
+    return ValidateCoverPathCHROMIUM(context, path, coverMode);
+}
+
+bool ValidateCoverStrokePathCHROMIUM(Context *context, GLuint path, GLenum coverMode)
+{
+    return ValidateCoverPathCHROMIUM(context, path, coverMode);
+}
+
 bool ValidateCoverPathCHROMIUM(Context *context, GLuint path, GLenum coverMode)
 {
     if (!context->getExtensions().pathRendering)
@@ -3528,7 +3538,7 @@
            ValidateCoverPathCHROMIUM(context, path, coverMode);
 }
 
-bool ValidateIsPathCHROMIUM(Context *context)
+bool ValidateIsPathCHROMIUM(Context *context, GLuint path)
 {
     if (!context->getExtensions().pathRendering)
     {