Revert "Use a constexpr array for es3 copy conversion table."

This reverts commit f30808db86.

Reason for revert: build/android/gyp/assert_static_initializers.py thinks this adds a static initializer.

See https://ci.chromium.org/p/chromium/builders/try/android-marshmallow-arm64-rel/208664

Need to revert since this is blocking the roll.

Original change's description:
> Use a constexpr array for es3 copy conversion table.
> 
> With the relaxed C++14 constexpr rules allowed in Chromium, we can
> use a constexpr sorted array to store our table data. This can lead
> to very fast lookups while being more maintanable than using auto-
> generator scripts for every lookup table.
> 
> Note that to be sure this syntax is permitted, we should land this
> through the bots and let it sit for a little while.
> 
> Bug: angleproject:1389
> Change-Id: I9395c40276470108ce3e5786d8f1b8d85462c517
> Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/777544
> Commit-Queue: Jamie Madill <jmadill@google.com>
> Reviewed-by: Yuly Novikov <ynovikov@chromium.org>

TBR=ynovikov@chromium.org,jmadill@google.com,syoussefi@chromium.org,jmadill@chromium.org

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

Bug: angleproject:1389
Change-Id: I482729b6f16975896b0e5c29999f9a081056e800
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/1506238
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org>
Commit-Queue: Jamie Madill <jmadill@chromium.org>

scripts/run_code_generation.py

@@ -93,6 +93,12 @@ generators = {
         auto_script('scripts/generate_loader.py'),
     'GL/EGL entry points':
         auto_script('scripts/generate_entry_points.py'),
+    'GL copy conversion table': {
+        'inputs': [
+            'src/libANGLE/es3_copy_conversion_formats.json',
+        ],
+        'script': 'src/libANGLE/gen_copy_conversion_table.py',
+    },
     'GL format map': {
         'inputs': [
             'src/libANGLE/es3_format_type_combinations.json',