Revert "Enable building GLES backend on Android"

This reverts commit c0b187c4c80781fdbb7eefa4aa84b4999f391b5f.

Reason for revert: Suspect cause of revert https://crrev.com/c/4837514

Original change's description:
> Enable building GLES backend on Android
>
> Doing so takes a dependency on dawn_use_angle because
> native GLES android drivers are buggy. dawn_use_angle
> itself akes a dependency on either not being Android,
> or being a component build. For testing, this is fine
> for now because tests run in component builds.
> Official builds are static which will disable ANGLE on
> Android which will also disable the GLES backend.
>
> Bug: 1453445
> Change-Id: I169fdd1b66e25708e349fcc000e6adbf7cb6dbff
> Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/149222
> Reviewed-by: Gregg Tavares <gman@chromium.org>
> Reviewed-by: Stephen White <senorblanco@chromium.org>
> Commit-Queue: Austin Eng <enga@chromium.org>
> Auto-Submit: Austin Eng <enga@chromium.org>
> Kokoro: Kokoro <noreply+kokoro@google.com>

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: 1453445
Change-Id: Idee208628dac24797f56488b0fc5abc657e7abd8
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/149742
Bot-Commit: rubber-stamper@appspot.gserviceaccount.com <rubber-stamper@appspot.gserviceaccount.com>
Auto-Submit: Austin Eng <enga@chromium.org>
Kokoro: Austin Eng <enga@chromium.org>
Commit-Queue: rubber-stamper@appspot.gserviceaccount.com <rubber-stamper@appspot.gserviceaccount.com>
diff --git a/scripts/dawn_features.gni b/scripts/dawn_features.gni
index 781fa43..6736f88 100644
--- a/scripts/dawn_features.gni
+++ b/scripts/dawn_features.gni
@@ -39,9 +39,7 @@
   # libGLESv2.so, apparently without regard for the use_static_angle=true
   # GN variable. Chromium's linker on Android disallows production of more
   # than one shared object per target (?).
-  # For now, ANGLE and thus the GLES backend are only enabled for component
-  # builds on Android.
-  dawn_use_angle = !is_android || is_component_build
+  dawn_use_angle = !is_android
 
   # Enables SwiftShader as the fallback adapter. Requires dawn_swiftshader_dir
   # to be set to take effect.
@@ -85,11 +83,8 @@
   # Enables the compilation of Dawn's OpenGLES backend
   # (WebGPU/Compat subset)
   # Disables OpenGLES when compiling for UWP, since UWP only supports d3d
-  # Disables OpenGLES when not using ANGLE on Android. Native GLES drivers
-  # are buggy and require ANGLE's workarounds.
   dawn_enable_opengles =
-      (is_linux && !is_chromeos) || (is_win && !dawn_is_winuwp) ||
-      (is_android && dawn_use_angle)
+      (is_linux && !is_chromeos) || (is_win && !dawn_is_winuwp)
 
   # Enables the compilation of Dawn's Vulkan backend
   # Disables vulkan when compiling for UWP, since UWP only supports d3d