Automated g4 rollback of changelist 162220754.

*** Reason for rollback ***

app-engine has a buggy implementation of FileInputStream.available() which is throwing IOException

*** Original change description ***

Implement ByteSource.asCharSource(charset).read() using the decoding string constructor instead of streaming the contents into a StringBuilder.

this allows us to avoid a number of copies that are currently happening for each character (1. into a temporary CharBuffer, 2. into a StringBuilder, 3 into the String char[]) and replace it with simply whatever is required by ByteSource.read() and the String(byte[], charset) constructor.  For certain ByteSource implementations (like FileByteSource) Byte...

***

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=162245286

android/guava/src/com/google/common/io/ByteSource.java

@@ -455,18 +455,6 @@ public Reader openStream() throws IOException {
       return new InputStreamReader(ByteSource.this.openStream(), charset);
     }
 
-    @Override
-    public String read() throws IOException {
-      // Reading all the data as a byte array is more efficient than the default read()
-      // implementation because:
-      // 1. the string constructor can avoid an extra copy most of the time by correctly sizing the
-      //    internal char array (hard to avoid using StringBuilder)
-      // 2. we avoid extra copies into temporary buffers altogether
-      // The downside is that this will cause us to store the file bytes in memory twice for a short
-      // amount of time.
-      return new String(ByteSource.this.read(), charset);
-    }
-
     @Override
     public String toString() {
       return ByteSource.this.toString() + ".asCharSource(" + charset + ")";

guava/src/com/google/common/io/ByteSource.java

@@ -455,18 +455,6 @@ public Reader openStream() throws IOException {
       return new InputStreamReader(ByteSource.this.openStream(), charset);
     }
 
-    @Override
-    public String read() throws IOException {
-      // Reading all the data as a byte array is more efficient than the default read()
-      // implementation because:
-      // 1. the string constructor can avoid an extra copy most of the time by correctly sizing the
-      //    internal char array (hard to avoid using StringBuilder)
-      // 2. we avoid extra copies into temporary buffers altogether
-      // The downside is that this will cause us to store the file bytes in memory twice for a short
-      // amount of time.
-      return new String(ByteSource.this.read(), charset);
-    }
-
     @Override
     public String toString() {
       return ByteSource.this.toString() + ".asCharSource(" + charset + ")";