Add missing {}s to conditionals & loops

This was necessary after:
44257cb8 apply clang-format

Which made some single-line statements into multi-line. Using braces on
multi-line statements better conforms with the Google style guide.

Bug: 433996651
Change-Id: I615c0ecf3b94571f67fceadfe8c15914aea45ccb

src/dsp/alpha_processing.c

@@ -355,22 +355,25 @@ static void ExtractGreen_C(const uint32_t* WEBP_RESTRICT argb,
 //------------------------------------------------------------------------------
 
 static int HasAlpha8b_C(const uint8_t* src, int length) {
-  while (length-- > 0)
+  while (length-- > 0) {
     if (*src++ != 0xff) return 1;
+  }
   return 0;
 }
 
 static int HasAlpha32b_C(const uint8_t* src, int length) {
   int x;
-  for (x = 0; length-- > 0; x += 4)
+  for (x = 0; length-- > 0; x += 4) {
     if (src[x] != 0xff) return 1;
+  }
   return 0;
 }
 
 static void AlphaReplace_C(uint32_t* src, int length, uint32_t color) {
   int x;
-  for (x = 0; x < length; ++x)
+  for (x = 0; x < length; ++x) {
     if ((src[x] >> 24) == 0) src[x] = color;
+  }
 }
 
 //------------------------------------------------------------------------------

src/dsp/alpha_processing_sse2.c

@@ -274,8 +274,9 @@ static int HasAlpha8b_SSE2(const uint8_t* src, int length) {
     const int mask = _mm_movemask_epi8(bits);
     if (mask != 0xffff) return 1;
   }
-  for (; i < length; ++i)
+  for (; i < length; ++i) {
     if (src[i] != 0xff) return 1;
+  }
   return 0;
 }
 
@@ -314,8 +315,9 @@ static int HasAlpha32b_SSE2(const uint8_t* src, int length) {
     const int mask = _mm_movemask_epi8(bits);
     if (mask != 0xffff) return 1;
   }
-  for (; i <= length; i += 4)
+  for (; i <= length; i += 4) {
     if (src[i] != 0xff) return 1;
+  }
   return 0;
 }
 
@@ -337,8 +339,9 @@ static void AlphaReplace_SSE2(uint32_t* src, int length, uint32_t color) {
     _mm_storeu_si128((__m128i*)(src + i + 0), _mm_or_si128(d0, e0));
     _mm_storeu_si128((__m128i*)(src + i + 4), _mm_or_si128(d1, e1));
   }
-  for (; i < length; ++i)
+  for (; i < length; ++i) {
     if ((src[i] >> 24) == 0) src[i] = color;
+  }
 }
 
 // -----------------------------------------------------------------------------

src/mux/muxread.c

@@ -278,9 +278,10 @@ WebPMux* WebPMuxCreateInternal(const WebPData* bitstream, int copy_data,
         ChunkRelease(&chunk);
         goto PushImage;
       default:  // A non-image chunk.
-        if (wpi->is_partial)
+        if (wpi->is_partial) {
           goto Err;  // Encountered a non-image chunk before
                      // getting all chunks of an image.
+        }
         if (chunk_list_ends[id] == NULL) {
           chunk_list_ends[id] =
               MuxGetChunkListFromId(mux, id);  // List to add this chunk.