[buffer_cache] swap begin and end expansion, don't clear runtime buffer

avoids filling the new buffer with zeroes (saves bandwidth)

also reduces relocation in case the old buffer ever gets too small

Co-authored-by: wildcard <nubieluv@gmail.com>
Signed-off-by: crueter <crueter@eden-emu.dev>

src/video_core/buffer_cache/buffer_cache.h

@@ -265,7 +265,7 @@ bool BufferCache<P>::DMAClear(GPUVAddr dst_address, u64 amount, u32 value) {
     const BufferId buffer = FindBuffer(*cpu_dst_address, static_cast<u32>(size));
     Buffer& dest_buffer = slot_buffers[buffer];
     const u32 offset = dest_buffer.Offset(*cpu_dst_address);
-    runtime.ClearBuffer(dest_buffer, offset, size, value);
+    // runtime.ClearBuffer(dest_buffer, offset, size, value);
     dest_buffer.MarkUsage(offset, size);
     return true;
 }
@@ -1349,10 +1349,10 @@ typename BufferCache<P>::OverlapResult BufferCache<P>::ResolveOverlaps(DAddr dev
             // as a stream buffer. Increase the size to skip constantly recreating buffers.
             has_stream_leap = true;
             if (expands_right) {
-                expand_begin(CACHING_PAGESIZE * 128);
+                expand_end(CACHING_PAGESIZE * 128);
             }
             if (expands_left) {
-                expand_end(CACHING_PAGESIZE * 128);
+                expand_begin(CACHING_PAGESIZE * 128);
             }
         }
     }