Plumb through out_row byte length so we can assert we stay underneath it.

src/opts/SkBitmapProcState_arm_neon.cpp

Index: src/opts/SkBitmapProcState_arm_neon.cpp
diff --git a/src/opts/SkBitmapProcState_arm_neon.cpp b/src/opts/SkBitmapProcState_arm_neon.cpp
index 08b83ea574c36d02d5cb868ea76a85f9a240aef9..d8a17d8dd790ea5b8551738dcd83593ed670a030 100644
--- a/src/opts/SkBitmapProcState_arm_neon.cpp
+++ b/src/opts/SkBitmapProcState_arm_neon.cpp
@@ -389,7 +389,8 @@ void convolveVertically_neon(const SkConvolutionFilter1D::ConvolutionFixed* filt
 // refer to that function for detailed comments.
 void convolve4RowsHorizontally_neon(const unsigned char* srcData[4],
                                     const SkConvolutionFilter1D& filter,
-                                    unsigned char* outRow[4]) {
+                                    unsigned char* outRow[4],
+                                    size_t outRowBytes) {
 
     uint8x8_t coeff_mask0 = vcreate_u8(0x0100010001000100);
     uint8x8_t coeff_mask1 = vcreate_u8(0x0302030203020302);