Removed clamping from dithering (#56140)

tests: https://github.com/flutter/flutter/pull/157643
fixes revert from https://github.com/flutter/flutter/pull/153976

The pixel format will clamp if it needs to anyway so this isn't
necessary.

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diff --git a/impeller/compiler/shader_lib/impeller/dithering.glsl b/impeller/compiler/shader_lib/impeller/dithering.glsl
index e8e4e84..5494c4e 100644
--- a/impeller/compiler/shader_lib/impeller/dithering.glsl
+++ b/impeller/compiler/shader_lib/impeller/dithering.glsl
@@ -45,9 +45,6 @@
   // Apply the dither to the color.
   color.rgb += dither * kDitherRate;
 
-  // Clamp the color values to [0,1].
-  color.rgb = clamp(color.rgb, 0.0, 1.0);
-
   return color;
 }
 
diff --git a/impeller/tools/malioc.json b/impeller/tools/malioc.json
index aafabbc..787254a 100644
--- a/impeller/tools/malioc.json
+++ b/impeller/tools/malioc.json
@@ -586,7 +586,7 @@
             "shortest_path_cycles": [
               0.5,
               0.109375,
-              0.296875,
+              0.28125,
               0.5,
               0.0,
               0.25,
@@ -596,9 +596,9 @@
               "load_store"
             ],
             "total_cycles": [
-              1.4249999523162842,
+              1.40625,
               0.862500011920929,
-              1.4249999523162842,
+              1.40625,
               0.875,
               4.0,
               0.25,
@@ -636,7 +636,7 @@
             "longest_path_cycles": [
               0.5,
               0.109375,
-              0.125,
+              0.109375,
               0.5,
               0.0,
               0.25,
@@ -658,7 +658,7 @@
             "shortest_path_cycles": [
               0.5,
               0.109375,
-              0.125,
+              0.109375,
               0.5,
               0.0,
               0.25,
@@ -671,7 +671,7 @@
             "total_cycles": [
               0.5,
               0.109375,
-              0.125,
+              0.109375,
               0.5,
               0.0,
               0.25,
@@ -6298,7 +6298,7 @@
             "shortest_path_cycles": [
               0.5625,
               0.203125,
-              0.265625,
+              0.25,
               0.5625,
               0.0,
               0.25,
@@ -6308,9 +6308,9 @@
               "load_store"
             ],
             "total_cycles": [
-              0.71875,
+              0.699999988079071,
               0.40625,
-              0.71875,
+              0.699999988079071,
               0.5625,
               4.0,
               0.25,
@@ -6768,7 +6768,7 @@
             "shortest_path_cycles": [
               0.5625,
               0.21875,
-              0.28125,
+              0.265625,
               0.5625,
               0.0,
               0.25,
@@ -6778,9 +6778,9 @@
               "load_store"
             ],
             "total_cycles": [
-              0.71875,
+              0.699999988079071,
               0.421875,
-              0.71875,
+              0.699999988079071,
               0.625,
               4.0,
               0.25,