[HER-1904] H3: OOME after a few hours of previously non-problematic crawl

* Recorder
    use min(raw-buffer size, actual recorded byte size) for char buffer size
* TextUtils
    on recycleMatcher, dereference previous 'input'

commons/src/main/java/org/archive/util/Recorder.java

@@ -382,13 +382,28 @@ public class Recorder {
         InputStream ris = getContentReplayInputStream();
         ReplayCharSequence rcs =  new GenericReplayCharSequence(
                 ris,
-                this.getRecordedInput().getRecordedBufferLength()/2, 
+                calcRecommendedCharBufferSize(this.getRecordedInput()), 
                 this.backingFileBasename + RECORDING_OUTPUT_STREAM_SUFFIX,
                 requestedCharset);
         ris.close();
         return rcs;
     }
     
+    /**
+     * Calculate a recommended size for an in-memory decoded-character buffer
+     * of this content. We seek a size that is itself no larger (in 2-byte chars)
+     * than the memory already used by the RecordingInputStream's internal raw 
+     * byte buffer, and also no larger than likely necessary. So, we take the 
+     * minimum of the actual recorded byte size and the RecordingInputStream's
+     * max buffer size. 
+     * 
+     * @param inStream
+     * @return int length for in-memory decoded-character buffer
+     */
+    static protected int calcRecommendedCharBufferSize(RecordingInputStream inStream) {
+        return Math.min(inStream.getRecordedBufferLength()/2,(int)inStream.getSize());
+    }
+    
     /**
      * Get a raw replay of all recorded data (including, for example, HTTP 
      * protocol headers)

commons/src/main/java/org/archive/util/TextUtils.java

@@ -78,6 +78,8 @@ public class TextUtils {
     }
 
     public static void recycleMatcher(Matcher m) {
+        // while cached, eliminate reference to potentially-large prior 'input'
+        m.reset(""); 
         final Map<String,Matcher> matchers = TL_MATCHER_MAP.get();
         matchers.put(m.pattern().pattern(),m);
     }