Remove GL image support from SkSL

This was added to Ganesh briefly in 2016 for an experiment, then
reverted, and never used.

Change-Id: I65849aff53acc14f9adc7585398fd09363a4ed65
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/374376
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
diff --git a/src/sksl/SkSLRehydrator.cpp b/src/sksl/SkSLRehydrator.cpp
index e4a817c..9d91666 100644
--- a/src/sksl/SkSLRehydrator.cpp
+++ b/src/sksl/SkSLRehydrator.cpp
@@ -102,7 +102,6 @@
             int set = this->readS8();
             int builtin = this->readS16();
             int inputAttachmentIndex = this->readS8();
-            int format = this->readS8();
             int primitive = this->readS8();
             int maxVertices = this->readS8();
             int invocations = this->readS8();
@@ -111,9 +110,8 @@
             int key = this->readS8();
             int ctype = this->readS8();
             return Layout(flags, location, offset, binding, index, set, builtin,
-                          inputAttachmentIndex, (Layout::Format) format,
-                          (Layout::Primitive) primitive, maxVertices, invocations, marker, when,
-                          (Layout::Key) key, (Layout::CType) ctype);
+                          inputAttachmentIndex, (Layout::Primitive)primitive, maxVertices,
+                          invocations, marker, when, (Layout::Key)key, (Layout::CType)ctype);
         }
         default:
             SkASSERT(false);