Revert "Temporary hack to force text texture index varying to be float."

This reverts commit 038ba443a0824ae45e33bdc7552e322fecb78315.

Reason for revert: Perf data is in

Original change's description:
> Temporary hack to force text texture index varying to be float.
> 
> Previous experiment showed disabling integer support in GrShaderCaps
> improved ANGLE D3D11 ES3 perf.
> 
> Trying to determine if perf hit on ANGLE D3D11 ES3 is from
> integer vertex attribs and unpack operations in VS or from
> using an int varying to communicate the index to the FS.
> 
> Will revert this after observing trend on perf.skia.org.
> 
> Change-Id: I40f4c0397b1377922c3018be864c1b7048bcfba9
> Bug: skia:10644
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/315866
> Reviewed-by: Jim Van Verth <jvanverth@google.com>
> Commit-Queue: Brian Salomon <bsalomon@google.com>

TBR=jvanverth@google.com,bsalomon@google.com

Change-Id: I4b32ff2c2472a046769d68a468642aa63e79a0df
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: skia:10644
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/316082
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
diff --git a/src/gpu/effects/GrBitmapTextGeoProc.cpp b/src/gpu/effects/GrBitmapTextGeoProc.cpp
index 1c11e26..f960540 100644
--- a/src/gpu/effects/GrBitmapTextGeoProc.cpp
+++ b/src/gpu/effects/GrBitmapTextGeoProc.cpp
@@ -40,7 +40,7 @@
                 kFloat2_GrSLType, "AtlasSizeInv", &atlasDimensionsInvName);
 
         GrGLSLVarying uv(kFloat2_GrSLType);
-        GrSLType texIdxType = args.fShaderCaps->integerSupport() && !SK_FORCE_MULTITEX_ATLAS_IDX_VARYING_TO_FLOAT ? kInt_GrSLType : kFloat_GrSLType;
+        GrSLType texIdxType = args.fShaderCaps->integerSupport() ? kInt_GrSLType : kFloat_GrSLType;
         GrGLSLVarying texIdx(texIdxType);
         append_index_uv_varyings(args, btgp.numTextureSamplers(), btgp.inTextureCoords().name(),
                                  atlasDimensionsInvName, &uv, &texIdx, nullptr);