Correct some spellings.

Test: mma
Change-Id: Icc49a4ee76f12d302ed18982d334f2f70b7263a8
diff --git a/payload_generator/extent_ranges_unittest.cc b/payload_generator/extent_ranges_unittest.cc
index 3705bac..d9dd467 100644
--- a/payload_generator/extent_ranges_unittest.cc
+++ b/payload_generator/extent_ranges_unittest.cc
@@ -304,7 +304,7 @@
 }
 
 TEST(ExtentRangesTest, FilterExtentRangesMultipleRanges) {
-  // Two overlaping extents, with three ranges to remove.
+  // Two overlapping extents, with three ranges to remove.
   vector<Extent> extents {
       ExtentForRange(10, 100),
       ExtentForRange(30, 100) };
diff --git a/payload_generator/filesystem_interface.h b/payload_generator/filesystem_interface.h
index b1506e4..08dfd19 100644
--- a/payload_generator/filesystem_interface.h
+++ b/payload_generator/filesystem_interface.h
@@ -19,9 +19,9 @@
 
 // This class is used to abstract a filesystem and iterate the blocks
 // associated with the files and filesystem structures.
-// For the purposes of the update payload generation, a filesystem is a formated
-// partition composed by fixed-size blocks, since that's the interface used in
-// the update payload.
+// For the purposes of the update payload generation, a filesystem is a
+// formatted partition composed by fixed-size blocks, since that's the interface
+// used in the update payload.
 
 #include <sys/stat.h>
 #include <sys/types.h>
diff --git a/payload_generator/payload_generation_config.h b/payload_generator/payload_generation_config.h
index ca6fb04..d64bf35 100644
--- a/payload_generator/payload_generation_config.h
+++ b/payload_generator/payload_generation_config.h
@@ -154,7 +154,7 @@
   // if is_full is false, so we are requested a delta payload.
   ImageConfig source;
 
-  // Wheter the requested payload is a delta payload.
+  // Whether the requested payload is a delta payload.
   bool is_delta = false;
 
   // The major/minor version of the payload.