[SurfaceFlinger] Apply legacy saturation matrix globally for Display P3.

We disallow legacy saturation matrix since this commit. For those do
have such a matrix, instead of applying it between sRGB->P3 conversion,
we apply it on P3. This means P3 and HDR tone mapped to P3 are also
saturated.

Bug: 110840428
Test: See red/orange scene through Camera ViewFinder, take a picture,
      check the picture in Photos App, the red/orange should have
      similar saturation.
Change-Id: I335b39888a76c7e411d9e03d9ad71448cbd7c05f
Merged-In: I335b39888a76c7e411d9e03d9ad71448cbd7c05f
diff --git a/services/surfaceflinger/RenderEngine/Program.cpp b/services/surfaceflinger/RenderEngine/Program.cpp
index 95adaca..fe536f0 100644
--- a/services/surfaceflinger/RenderEngine/Program.cpp
+++ b/services/surfaceflinger/RenderEngine/Program.cpp
@@ -135,22 +135,13 @@
         glUniform4fv(mColorLoc, 1, color);
     }
     if (mInputTransformMatrixLoc >= 0) {
-        // If the input transform matrix is not identity matrix, we want to merge
-        // the saturation matrix with input transform matrix so that the saturation
-        // matrix is applied at the correct stage.
-        mat4 inputTransformMatrix = mat4(desc.mInputTransformMatrix) * desc.mSaturationMatrix;
+        mat4 inputTransformMatrix = mat4(desc.mInputTransformMatrix);
         glUniformMatrix4fv(mInputTransformMatrixLoc, 1, GL_FALSE, inputTransformMatrix.asArray());
     }
     if (mOutputTransformMatrixLoc >= 0) {
         // The output transform matrix and color matrix can be combined as one matrix
         // that is applied right before applying OETF.
         mat4 outputTransformMatrix = desc.mColorMatrix * desc.mOutputTransformMatrix;
-        // If there is no input transform matrix, we want to merge the saturation
-        // matrix with output transform matrix to avoid extra matrix multiplication
-        // in shader.
-        if (mInputTransformMatrixLoc < 0) {
-            outputTransformMatrix *= desc.mSaturationMatrix;
-        }
         glUniformMatrix4fv(mOutputTransformMatrixLoc, 1, GL_FALSE,
                            outputTransformMatrix.asArray());
     }