ENGINES: Continue to check file presence after a hash/size mismatch

If an early file in the game's signature list has a hash/size
mismatch, it is still necessary to continue to check the rest of
the candidate files for existence, since the non-existence of
candidate files is supposed to disqualify a game description as
matching a game to an unknown variant.

By quitting the file check early, the detector had been allowing
descriptions to randomly match if there happened to be an early
file in the detection list with the right name but wrong hash/size,
even if some of the other signature files did not exist at all.

engines/advancedDetector.cpp

@@ -466,6 +466,7 @@ ADGameDescList AdvancedMetaEngine::detectGame(const Common::FSNode &parent, cons
 
 		bool allFilesPresent = true;
 		int curFilesMatched = 0;
+		bool hashOrSizeMismatch = false;
 
 		// Try to match all files for this game
 		for (fileDesc = g->filesDescriptions; fileDesc->fileName; fileDesc++) {
@@ -477,16 +478,21 @@ ADGameDescList AdvancedMetaEngine::detectGame(const Common::FSNode &parent, cons
 				break;
 			}
 
+			if (hashOrSizeMismatch)
+				continue;
+
 			if (fileDesc->md5 != NULL && fileDesc->md5 != filesProps[tstr].md5) {
 				debug(3, "MD5 Mismatch. Skipping (%s) (%s)", fileDesc->md5, filesProps[tstr].md5.c_str());
 				fileMissing = true;
-				break;
+				hashOrSizeMismatch = true;
+				continue;
 			}
 
 			if (fileDesc->fileSize != -1 && fileDesc->fileSize != filesProps[tstr].size) {
 				debug(3, "Size Mismatch. Skipping");
 				fileMissing = true;
-				break;
+				hashOrSizeMismatch = true;
+				continue;
 			}
 
 			debug(3, "Matched file: %s", tstr.c_str());